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HAL Id: inria-00543948

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Submitted on 6 Dec 2010

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logarithms (1827)

Denis Roegel

To cite this version:

Denis Roegel. A reconstruction of Charles Babbage’s table of logarithms (1827). [Research Report] 2010. �inria-00543948�

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A reconstruction of

Charles Babbage’s

table of logarithms

(1827)

Denis Roegel

6 December 2010

This document is part of the LOCOMAT project: http://www.loria.fr/~roegel/locomat.html

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This document contains a reconstruction of Charles Babbage’s table of (decimal) logarithms, whose first edition was published in 1827. It is not an exact facsimile, but an improved version, keeping the format of the 1827 edition (including the title and errata), but with a correct listing of the logarithm values.

Babbage’s interest in tables was closely related to his interest for the mechanical computation of tables [4, 15]. But Babbage’s ta-bles were gathered and improved from the tata-bles of Callet [2], Gar-diner [8], Hutton [13], Vega [20], Vlacq [22], and others, using only manual computations, as did many other compilers over the years. The making of Babbage’s tables was described by Martin Camp-bell-Kelly [3] and it shows in particular the relationship between his tables and the great tables computed in 1793–1795 by a team led by Prony for the French Cadastre [14].

Several editions of Babbage’s tables were published between 1827 and 1889, including German and Hungarian editions, each edition correcting errors of the previous editions and using the original

stereotype plates.1 Two more editions were published in 1912 and

1915, but apparently without using the original stereotype plates which had probably been lost or discarded [3, p. 166]. Whereas the focus of the corrections lied on the main table values, it is inter-esting to observe that the list of constants which was given at the end of the book contained numerous errors which mostly remained uncorrected. In this reconstruction we have corrected the values of the logarithms, using the constants given by Babbage (such as the ratio between a French and an English foot), except in the case of

π-based expressions where we strived to give more accurate values

of the logarithms.

We have also corrected some obvious layout errors in Babbage’s introduction and preface. We took some leeway with the page divi-sions which do not occur exactly where Babbage had put them. The tables, however, try to mimick the original tables as best as possible.

1

See Fletcher et al. [6, pp. 785–786] for a comprehensive errata. There are in particular many last digit errors beyond 100000, a section that Babbage copied from Callet, who never troubled about last-figure accuracy. The 1827, 1831, 1834, and 1841 English editions are available on google books (id: piNNAAAAMAAJ, P11HAAAAYAAJ, nzUAAAAAQAAJ, and 6yXOAAAAMAAJ).

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them by two different ways, which resulted in exactly the same 108000 values. Our tables can therefore be certified and do not contain any error, whereas Babbage’s table contained a few errors which were corrected in subsequent impressions.

Unlike previous logarithm tables, such as those by Callet [2] or Vega [21], Babbage’s tables also show how the last digit was rounded, or more exactly whether the last digit is correct or not. Babbage put a dot under a figure which is in excess to the real figure. This feature had to be taken into account in our recomputation.

Also, unlike the other tables we have reconstructed, the loga-rithms of Babbage’s table were first recomputed using Philip A. Nel-son’s bc program with an accuracy of 15 digits after the decimal point [16]. These values were truncated to 7 or 8 decimals (depend-ing on the part of Babbage’s table) and manually (i.e., not us(depend-ing bc) rounded according to the remaining decimals. Assuming there is at most an error of one unit on the 15th place, the rounded value would only be incorrect in case the figures following the truncated ones were really 49999999 instead of 50000000 given by bc. There are however no such cases on the range 1–108000. The closest calls are the following two logarithm values, with the digits 49999 and 50000 after the 7th decimal place:

log(22397) = 4.35018984999933... log(61663) = 4.79002465000047...

Here, had we computed log(22397) with 11 digits, bc would have returned 4.35018985000 which is incorrectly rounded. There are no cases with 499999 or 500000 after the 7th or 8th decimal places over the range 1–108000.

It is only in a second stage that we used the GNU mpfr multiple-precision floating-point library developed at INRIA [7]. We have similarly computed the values of the logarithms with sufficient bi-nary digits and rounded them to their nearest values. These values were then converted to their decimal counterpart and the rounding was done manually, by checking the digit following the 7th or 8th place, knowing that there wouldn’t be any closer calls than those mentioned above. However, a more general computation could have been achieved by detecting such close calls on the fly, and increasing

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certainty. Such a procedure may be necessary for more accurate tables.

These two different means of computing the 108000 logarithm values agreed perfectly, both on their values, and on the cases where the rounded value differs from the truncated one.

Another challenge in the generation of the tables were the in-terpolation tables. These small tables are not positioned at totally regular positions, and there are a number of idiosyncrasies. Bab-bage normally puts the table head on the line where that difference first occurs. For instance, difference ∆ should first be used when

log(x + 1) − log x = (∆ + 0.5) · 10−7 (in the first part of the tables).

This leads to

x 10

7

(∆ + 0.5) · ln 10

For ∆ = 407, we find x = 10658. The interpolation tables are mostly positioned correctly, or almost correctly in the first part of the ta-bles (10000–99999), but the second part (100000–107999) contains numerous positioning errors. Babbage puts for instance the differ-ence 407 around 10671(0) in the second part of the tables (page 199) which is 13 lines wrong. This problem was still not corrected in the 1841 edition, nor presumably in later ones. A special case in the first part is that of 347 on page 11, because it should actually start on page 10. We have decided to correct all these problems and have put the differences at the correct positions, as much as was possible. We did however not move the interpolation table for 347, because it really starts at 12498, and therefore concerns only two values on page 10. Also, the differences valid at the beginning of the pages 191–198 have not been shown, because of lack of space. Neither did Babbage.

There is a vast literature on the tables of logarithms, and nu-merous tables have been produced since the invention of loga-rithms at the beginning of the 17th century. In the subsequent pages, we give excerpts of some important tables from the 18th cen-tury [1, 2, 8, 12, 19, 21]. Table makers copied heavily from eachother, and tables such as those of Callet [2] were initially really those of Gardiner, before they took a life of their own.

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previous tables. Most notably, he introduced small digits to indicate when the third decimal place of a logarithm value changed (which not all table makers did), and the dots under figures which were rounded and different from the truncated figures (which none of the table makers before Babbage seems to have done).

We thank Paul Zimmermann for some advice on the use of the

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The following list covers the most important references2 related to

Babbage’ tables. Not all items of this list are mentioned in the text, and the sources which have not been seen are marked so. We have added notes about the contents of the articles in certain cases.

[1] Henry Briggs, John Wallis, Edmund Halley, and Abraham Sharp. Mathematical tables, etc. London: R. and W. Mount, T. Page, 1717.

[2] Jean-François Callet. Tables portatives de logarithmes, etc.

Paris: Firmin Didot, 1795. [There have been numerous later

printings of these tables.]

[3] Martin Campbell-Kelly. Charles Babbage’s table of logarithms (1827). Annals of the history of computing, 10(3):159–169, 1988.

[4] Martin Campbell-Kelly, editor. The works of Charles Babbage, volume 2: The difference engine and table making. London: William Pickering, 1989.

[5] Martin Campbell-Kelly, Mary Croarken, Raymond Flood, and Eleanor Robson, editors. The history of mathematical tables: from Sumer to spreadsheets. Oxford: Oxford University Press, 2003.

[6] Alan Fletcher, Jeffery Charles Percy Miller, Louis Rosenhead, and Leslie John Comrie. An index of mathematical tables.

Oxford: Blackwell scientific publications Ltd., 1962. [2nd edition

(1st in 1946), 2 volumes]

2Note on the titles of the works:

Original titles come with many id-iosyncrasies and features (line splitting, size, fonts, etc.) which can often not be reproduced in a list of references. It has therefore seemed pointless to capitalize works according to conventions which not only have no relation with the original work, but also do not restore the title entirely. In the following list of references, most title words (except in German) will therefore be left uncapitalized. The names of the authors have also been homogenized and initials expanded, as much as possible.

The reader should keep in mind that this list is not meant as a facsimile of the original works. The original style information could no doubt have been added as a note, but we have not done it here.

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Pélissier, and Paul Zimmermann. MPFR: A multiple-precision binary floating-point library with correct rounding. ACM Transactions on Mathematical Software, 33(2), 2007.

[8] William Gardiner. Tables of logarithms, for all numbers from 1 to 102100, and for the sines and tangents to every ten

seconds of each degree in the quadrant; as also, for the sines of the first 72 minutes to every single second: with other useful and necessary tables. London: G. Smith, 1742.

[9] James Whitbread Lee Glaisher. Report of the committee on

mathematical tables. London: Taylor and Francis, 1873. [Also

published as part of the “Report of the forty-third meeting of the British Association for the advancement of science,” London: John Murray, 1874.]

[10] Norman T. Gridgeman. Babbage, Charles. In

Charles Coulston Gillispie, editor, Dictionary of Scientific Biography, volume 1. New York: Charles Scribner’s Sons,

1971. [not seen]

[11] James Henderson. Bibliotheca tabularum mathematicarum, being a descriptive catalogue of mathematical tables. Part I: Logarithmic tables (A. Logarithms of numbers), volume XIII of Tracts for computers. London: Cambridge University Press, 1926.

[12] Charles Hutton. Mathematical tables: containing common, hyperbolic, and logistic logarithms, also sines, tangents,

secants, and versed-sines, etc. London: G. G. J., J. Robinson, and R. Baldwin, 1785.

[13] Charles Hutton. Mathematical tables, etc. London, 1811. [fifth

edition]

[14] Pierre Alexandre Francisque Lefort. Description des grandes tables logarithmiques et trigonométriques, calculées au bureau du cadastre, sous la direction de Prony, et exposition des méthodes et procédés mis en usage pour leur construction. Annales de l’Observatoire impérial de Paris, 4

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Johann Müller, Charles Babbage and Georg and Edvard Scheutz. Cambridge: Massachusetts Institute of Technology, 1990.

[16] Philip A. Nelson. bc, an arbitrary precision calculator

language, 1997. [version 1.06]

[17] Denis Roegel. A reconstruction of De Decker-Vlacq’s tables in the Arithmetica logarithmica (1628). Technical report,

LORIA, Nancy, 2010. [This is a recalculation of the tables of [22].]

[18] Denis Roegel. The great logarithmic and trigonometric tables of the French Cadastre: a preliminary investigation. Technical report, LORIA, Nancy, 2010.

[19] Henry Sherwin. Sherwin’s mathematical tables, etc. London:

William Mount and Thomas Page, 1742. [third edition]

[20] Georg Vega. Thesaurus logarithmorum completus. Leipzig: Weidmann, 1794.

[21] Georg Vega. Logarithmisch-trigonometrische Tafeln nebst andern zum Gebrauch der Mathematik eingerichteten Tafeln und Formeln. Leipzig: Weidmannischen Buchhandlung, 1797.

[volume 1]

[22] Adriaan Vlacq. Arithmetica logarithmica. Gouda: Pieter

Rammazeyn, 1628. [The introduction was reprinted in 1976 by Olms

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Babbage gave a brief description of his tables to the Astronomical Society of London in 1827, and we reproduce his communication be-low (Memoirs of the astronomical society of London, vol. III., Part I., 1827, pp. 65–67):

Notice respecting some Errors common to many Tables of Log-arithms. By Charles Babbage, Esq., Foreign Secretary of the Astronomical Society.

Read March 9, 1827.

Having lately printed a stereotype table of the logarithms of

natural numbers, for the use of the Survey of Ireland, I observed among the errors detected in various tables during the eight readings to which it was subjected, several which appeared common to many of them. This circumstance induced me to examine some other tables at the same numbers; and I find that there are six errors which are common to almost all tables: those of Vega, the recent impressions of Callet and my own, are the only ones entirely exempt. The following table shows the sixth and seventh figures, and in a few cases also the eighth, ninth and tenth figures, of the logarithms in the respective tables: the erroneous figures being indicaed by a bar placed above them.

24,626 38,962 57,628 57,629 63,747 67,951 Natural Numbers.

39751 13420 35875 10436 97412 58424 Vlacq, fol. Gouda . . . 1628

39751 13420 35875 10436 97412 58424 Vlacq, fol. London . . . 1633

39 13 35 10 97 58 E. Wingate, 12mo. London . . . 1633

397 134 359 104 974 584 Newton, fol. London . . . 1658

40 13 36 10 97 58 Sherwin, 8vo. 1st ed. London . . . . 1726

40 13 36 10 97 58 Sherwin, 8vo. 2nd ed. London . . . 1741

40 13 36 10 97 58 Sherwin, 8vo. 3rd ed. London . . . 1742

40 13 36 10 97 58 Gardiner, 4to. London . . . . 1742

40 13 36 10 97 58 Sherwin, 8vo. 4th ed. London . . . 1761

40 13 36 10 97 58 Sherwin, 8vo. 5th ed. London . . . 1770

40 13 36 10 97 58 Gardiner, 4to. Avignon . . . . 1770

40 13 36 10 97 58 Schulze, 8vo. Berlin . . . 1778

40 13 36 10 97 58 Gardiner, 4to. Fiorenze . . . 1782

39 12 36 10 97 58 Taylor, 4to. London . . . 1792

38751 12420 35475 10836 97512 58524 Vega, fol. Leipsic . . . 1794

40 13 36 10 97 58 Callet, 8vo. Paris . . . 1795

40 13 36 10 97 58 Delambre, Tab. Dec., 4to. Paris 1801 39 12 36 10 97 58 Hutton, 8vo. 4th ed. London . . . . 1804

39 12 36 10 97 58 Hutton, 8vo. 5th ed. London . . . . 1811

39 12 35 11 98 59 Vega, 8vo. 5th ed. Leipsic . . . 1820

39 12 36 10 97 58 Hutton, 8vo. 6th ed. London . . . . 1822

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system of copying which prevails in such works.

These six errors may be traced back to the tables of Vlacq printed at Gouda, 1628. The two first occur in the seventh figure, and are owing to the printer:—The third and fourth occur in the eighth place, and arise from the two type 4 and 8 having fallen out in the course of printing, and being interchanged when replaced:—The fifth and sixth may arise either from an error of the printer or of the calculator: the latter is the most probable supposition, particularly as regards the last; for the logarithm immediately succeeding it in

Vlacq’s table is also wrong, owing to the difference being added to

an incorrect logarithm. This error, however, does not continue to the next logarithm, which would have been wrong had it been formed by the addition of the difference to the last.

It is a singular circumstance that the last four errors in the above list all occur in the eighth place of figures; and that they are all of such a nature as to influence the seventh figure, in case tables should be formed from them consisting of that number of figures.

As the library of the Royal Society contains a table of logarithms printed in the Chinese character, which contains no indication or acknowledgement of its being copied from any other work, I was curious to compare it with European tables in the six cases alluded to. I found on examination that precisely the same errors occurred in the Chinese tables as those which I have noticed as being found in the tables of Vlacq. The conclusion from this fact is irresistible:— The Chinese tables were copied from those of Vlacq.

As these tables are of rare occurrence, a short account of them may not be uninteresting. The copy in the library of the Royal Soci-ety was presented to the SociSoci-ety by Pere Gaubil in 1750. It con-sists of two thin volumes; each containing the logarithms of 50,000 numbers; each page contains three columns of natural numbers, and three columns of their corresponding logarithms; each column con-sisting of fifty lines. The numbers begin at the end of the volume, and the first column is on the right hand side of the page: but, unlike the usual mode of writing the Chinese character, the figures read from left to right. There is no column of differences, nor any running title; and the volumes are without title-page, preface, or in-structions. They are printed on a beautiful thin yellow paper which is double, as is usual in Chinese books. The natural numbers are

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in black ink, but probably after them, as they occasionally fall upon and interfere with the black rules. The length of the printed part of each page is very nearly eight inches, and its breadth five and three quarters.

Another volume presented by the same donor accompanies these; it contains the logarithmic sines, cosines, tangents, and cotangents, to every ten seconds. It is printed on the same kind of paper as the former, and resembles it in many respects. It has a heading in red

ink; the length of the printed part of the page is 85

8 inches, and its

breadth 56

8. It is probably copied from the Trigonometria Artificialis

of Vlacq, which was printed in 1633. These tables do not appear to have been printed with much care, since I noticed two errors in the short examination I made of them.

These three volumes if bound together would form one moder-ate sized volume in royal octavo, and are comprised in a smaller space than any tables of an equal number of figures which have been printed in Europe.

March 5, 1827.

An account of the previous meeting is given in the Monthly no-tices of the astronomical society of London, vol. I., 1831, page 9:

At this meeting there was read, a “Notice respecting some errors

common to many tables of logarithms,” by Charles Babbage, Esq., Foreign Secretary of this Society. Mr. Babbage having lately printed a stereotype table of the logarithms of the natural numbers, for the use of the Trigonometrical Survey in Ireland, for the sake of greater accuracy subjected them to eight readings and comparisons with other tables. This cautious process led to the detection of various errors, which are common to almost all the tables; those of Vega, the last impressions of Callet, and Mr. Babbage’s own tables, being all that he has found free from the errors which he specifies. The tables subjected to this examination were those of Vlacq, Gouda, 1628, carried to ten figures; Vlacq, London, 1633; Wingate, London, 1633; Newton, in his Trig. Britan. 1658, to eight figures; Sherwin, London, 1726; 2nd ed. 1741; 3rd ed. 1742; Gardiner, London, 1742; Sherwin, 4th ed. 1761; 5th ed. 1770; Gardiner, Avignon, 1770; Schulze, Berlin,

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1794; Callet, (stereotype,) Paris, 1795; Callet, ditto, Paris, (tirage,) 1825; Hobert and Ideler, Berlein, 1799; Delambre, Tab. Dec. Paris, 1801; Hutton, 4th ed. London, 1804; 5th ed. 1811; Vega, Leipsic, 1820; Hutton, 6th ed., London, 1822; Babbage, London, 1827.— Mr. Babbage thinks that the errors which he has detected can only be attributed to the universal system of copying which prevails in such works.

The numbers and correct logarithms to seven places are as below:

Numbers. Logarithms. Vlacq’s last five figures.

24626 . . . 3913940 . . . 39751 38962 . . . 5906412 . . . 13420 57628 . . . 7606335 . . . 35875 57629 . . . 7606411 . . . 10436 63747 . . . 8044598 . . . 97412 67951 . . . 8321959 . . . 58424 From these the several tables specified may readily be corrected.

Mr. Babbage knowing that there was in the Library of the Royal Society a table of logarithms printed in the Chinese character, and which exhibits no indication or acknowledgment of its being copied from another work, was naturally desirous to compare it with Euro-pean tables. On doing so, he found that in the six cases above noted, errors occurred precisely as in the European tables; this furnishing an irresistible proof that the Chinese tables have an European origin.

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From time to time, Babbage’s tables are also cited in the litera-ture by others, sometimes in order to report misprints or errors. We give here some of these mentions.

• The Philosophical magazine, or Annals of Chemistry, Math-ematics, Astronomy, Natural History, and General Science, wrote (volume 1, number 6, June 1827, pp. 470–471):

note respecting mr. babbage’s logarithms. The logarithm of the number 24626, whose four last figures are 3939, is given among the errata printed at the end of the preface, to Mr. Babbage’s Logarithms.

The errata so stated can scarcely be considered as errors, since each copy contains the proper corrections. The history of that particular mistake may be useful as pointing out the manner in which they are sometimes introduced. Its origin in all the mod-ern tables arises from a misprint in Vlacq’s folio edition of 1628, in which a nine is printed instead of an eight in the 7th place of figures. In the first three readings of the proofs of Mr. Bab-bage’s tables, they were compared with tables corrected by his own copy of Vega, and this correction was included; and it was rightly printed 3939. During the next three readings by a different set of readers, copies of tables were accidentally em-ployed, in which this had been neglected to be corrected; it was consequently altered to 3940. The plates were now stereo-typed, and in the 7th and 8th reading it was again detected, and the source of its introduction traced. The only error at present known in these tables is the misprint in the logarithms of the number 13588, in which the fourth figure is a large unity instead of a small unity.

• In his article Correction of Errors found in several Mathemat-ical Tables (The American journal of science and arts, sec-ond series, volume V, number 15 (May 1848), pp. 398–401), A. D. Stanley wrote:

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months since, several errors were found by the writer in differ-ent tables which he had occasion to examine. A list of them is given below, for the use of thos who have copies of the tables referred to.

Babbage’s Table of Logarithms of Numbers: second edition; London, 1831

Log. 10354 (p. 6) The first of the figures 1082 should be in small type.

Log. 60676–7–8–9. Log. 70634–5–6–7–8–9.

 The cipher in each of the logarithms should be in small type.

(...)

• William Galbraith, On Logarithmic Tables (The Edinburgh new philosophical journal, vol. XXXIX, April 1845—October 1845, pp. 169–170) wrote:

Dear Sir,—It would be acceptable to those individuals who

use the following tables, to have it in their power to correct the following errors, which, I believe, are not so generally known as they ought to be.

(...) Callet,

Babbage, Hutton, Hülsse’s Vega,

)

No. 102467 log. 01058492 for 01058402. No. 106888 log. 02882995 for 02882895. (...)

In the first four, Callet seems to have committed the original errors, from which the others appear to have been copied with-out sufficient examination, though great pretensions are made by all to extreme care.

(...)

• the Astronomical Journal (vol. 4, iss. 78, p. 48, 1854) wrote: correction to babbage’s logarithm tables.

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No. 102467, Log is printed 01058492, instead of 01058402. • in 1863, Aug. Gernerth mentioned three errors (“Bemerkungen

über ältere und neuere mathematische Tafeln,” Zeitschrift für die österreichischen Gymnasien, 1863, VI. Heft, pp. 407–443): log. 102467 is given as ·01058492 but should be ·01058402, log. 103000 is given as ·01283723 but should be ·01283722, log. 106888 is given as ·02892995 but should be ·02892895

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The following pages show excerpts of some of the tables which have influenced Babbage, and the reader can easily see that Bab-bage’s work concerns some details in the presentation, as well as a great endeavour for accuracy.

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OF

LOGARITHMS

OF THE

NATURAL NUMBERS,

FROM

1 to 108000.

BY CHARLES BABBAGE, ESQ.

M.A. F.R.S. L. & E. M.R.I.A. F.C.P.S.

MEM. ASTRON. SOC. MEM. ACAD. DIJON, COR. PHILOMATH. SOC. PARIS, COR. MEMB. ACAD. MARSEILLES, AND ROYAL ACAD. BRUSSELS, &c.

STEREOTYPED.

LONDON :

PRINTED FOR J. MAWMAN, LUDGATE-STREET.

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In presenting to the public a new table of Logarithms, two things particularly demand the attention of the editor—their correctness, and the facility with which they can be used by computers. In order to give confidence in their accuracy, it is necessary that the calcula-tions should be true, and their results correctly printed; and that the means by which this has been attempted to be accomplished should be fully stated.

The following arrangement was adopted for the purpose of insur-ing accuracy in the printinsur-ing.

A copy of the stereotype logarithms of Callet was carefully read over with the folio edition (1794) of Vega’s logarithms, to ten figures, and whenever the last figure in Callet’s logarithms was found to have been increased, it was marked with red ink. All the terminal figures thus marked were to be printed with a dot below them.

Types were cast having dots below the figures, and also others with the figures smaller than those in the body of the table. These latter were to be employed whenever the third figure of the loga-rithms changed.

The proofs of the present tables were read three times: 1st, with the marked copy of Callet’s logarithms; 2dly, with a copy of Hut-ton’s logarithms, fourth edition, 1804; 3dly, with a copy of Vega’s logarithms, folio, 1794.

They were now received from the printer, and were again com-pared with the logarithms of Vega as far as 100,000; the last 8,000 being read with those of Callet. 5thly, The first 20,000 were read with those in the Trigonometria Artificialis of Briggs. Folio. Goudæ, 1633.

They were next returned to the printer, and stereotyped, and the proofs from the plates were read; 6thly, with the logarithms of Vega as far as 47,500; 7thly, with the whole of the logarithms of Gardiner, 4to. London, 1742; 8thly, with the logarithms of Taylor, 4to. 1792; and 9thly, by a different set of readers they were again read with the logarithms of Taylor.

I had experienced the accuracy of tables printed at the press i

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superintendent of that establishment, the present work is materially indebted.

In the table of logarithms beginning at 10,000, and terminating at 108,000, the readers, previous to the stereotyping, detected ten errors of figures, eight of which occurred in the first sheet, before the system of work, which Mr. Cox had arranged, had well got into action. Among the differences, there were four errors.

Amongst the dotted figures, which were much more difficult to correct, and which the printer had fewer means of making accurate, there were found eighteen erroneous.

From the circumstance of these logarithms being wanted for im-mediate use, it was necessary to print them as soon as possible, in order to allow of time for the ink to dry and harden previous to bind-ing. In the readings, after stereotyping, seven errors were discovered in the logarithms, and one in the differences. These have been cor-rected in the plates. For the whole of the readings subsequent to the third, I am indebted to the kindness of Lieutenant-Colonel Colby, under whose direction they were executed.

In the fourth reading, with Vega’s logarithms to ten figures, 93 cases were observed in which the last three figures in those tables were 500. As those tables were themselves true to the nearest unit, it was not certain whether, if these logarithms were given to a greater number of figures, the 8th, 9th, and 10th might not be 499, in which case the last figures of the table to seven figures, ought not to be increased and dotted.

Thus the logarithms of 1·0117 is ·005050517 500 ;

but the logarithm of the same number to seven figures is not ·0050518,

because the logarithm to twelve figures is ·0050517 499 93,

3

Now that of Mr. Clowes.

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figures is

·0050517.

In seventy-seven instances, the figures succeeding the seventh were 499 or 500.

In fourteen instances, those figures were 4999 or 5000. And in two cases, they were 49999 and 50000.

It became necessary therefore, in all these cases, to have the logarithms carried to more than ten figures.

In many of the earlier instances, the logarithms were calculated to fifteen figures; but as I found it necessary, during the progress of the impression, to visit Paris, I availed myself of that opportunity of consulting the great manuscript tables preserved at the Observatory, which were calculated under the direction of M. Prony.

Through the kindness of the Marquis Laplace, President of the Board of Longitude in France, of M. Bouvard, and of other members of that distinguished body, I enjoyed every facility for making the comparisons which were requisite for this purpose, as well as for making extracts necessary to me for other calculations.

Although the liberality with which these treasures of calculation are thrown open to those who may wish to avail themselves of them, and the attentions which such persons receive from every officer of the establishment in which they are deposited, deserve to be rec-ommended as models in all similar cases, I still may be permitted to express a wish, that so vast a monument of industry and of sci-ence should be rendered more useful, as well as more perfect and indestructible, by embodying it in stereotype plates.

With regard to those arrangements, on which the facility of using a table depends, I shall offer a few remarks, although at the hazard of seeming to bestow more attention than may be necessary on a subject which may appear of trifling importance.

With the assistance of my friend Lieutenant-Colonel Colby, I ex-amined a considerable collection of tables of different kinds, with the view of discovering on what typographical circumstances perspicuity depended.

Wherever we observed any remarkable for clearness or for obscu-rity, we endeavoured to discover and to note the cause of such an appearance. From this examination resulted the following collection

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were of more doubtful propriety.

1st. The clearness or facility of reading, does not depend on the size of the type alone, but on the proportion of the type to the interval between the lines.

2nd. Figures of the same or nearly the same height, are preferable to those in which some of the digits rise above and others fall below the line, because they interfere less with the space between the lines. This becomes still more necessary, if from any cause it is desirable to distinguish some of the figures by means of a bar, a dot, or any other sign, placed either above or below them.

3rd. The lines dividing vertical columns should not be placed in the middle of the space between the columns, but should be nearer the preceding column. The effect of this mode of placing the vertical lines is to leave a white line at the commencement of every column, which not only assists in directing the eye, but makes the adjacent dark line more distinct. The same principle is applicable to the case of a table divided by horizontal lines.

4th. When some parts of a table are to be separated from the

rest more decisively than by the ordinary lines,4 a single dark line

is much more conspicuous than two fainter lines adjacent to each other; and, if necessary, for further distinction, another, and much darker line, may be employed with success.

5th. Those figures which are first sought on entering a table, ought to be so distinguished, either by position or by magnitude, as to strike the eye readily. Since their position is not always left to our choice, we must sometimes employ type of different kinds or magni-tudes for this purpose. Colour might be a convenient distinction in some cases, but the difficulties which occur in printing with two or more colours will prevent its frequent employment. In the present tables, the four first figures of the number sought are printed with large type, in order that they may be easily found. For the same rea-son, the figures at the top and bottom of the page are also larger than the rest. As the natural numbers are in large type, they will readily catch the eye in turning over the pages; it was therefore thought ad-visable to put at the top of the left-hand page the three first figures

4

As in the case of the first five columns of a table of logarithms, which are separated from the last five.

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the finding of the page in which a number or a logarithm occurs equally easy.

By this arrangement, the right-hand pages will have the number nearest to the corner, instead of the logarithm; but this was not thought an objection of sufficient importance to justify a deviation from the order in which they are placed on the opposite pages.

6th. In most instances it is better to print the figures denoting the tens, the hundreds, or the thousands, although they may remain the same for several lines. The reason of this rule is, that the eye has

not to travel so far to acquire the information sought in the table.5

The arrangement of the table was a subject of attentive consider-ation, and I availed myself of the observations of many of my friends who had great experience in the use of tables. The most difficult question to decide upon, was the mode by which the change in the third figure of a logarithm should be indicated, when it does not occur precisely at the end of a line.

The method used by Callet, of bringing down the remainder of the line so as to leave a blank space between it and the preceding one, had many admirers. It is, however, liable to some objections: it prevents the occurrence of the blank intervals at regular periods, (usually once in five lines,) an inconvenience of some moment, and which increases the time required for using the table. It is also at variance with a general principle which I found it necessary to establish, in order to decide on a proper mode of marking this cir-cumstance. The principle alluded to is, that

7th. Whatever mode be adopted for marking the change of the third figure, it ought to be of such a nature that if the four last figures of any logarithm be selected, in the middle or in any part of a page, it shall be immediately visible without reference to any other part of the table, whether the third figure has changed or not. The blank space marking the break in the line, employed by Callet, agrees with this principle at the commencement of his tables; but throughout the greater part, there are blank spaces which do not indicate any change in the third figure. Another objection to his mode is, that the figures of the logarithms cease to be opposite those of their corresponding

5

This rule was not considered until it was too late to comply with it in these tables.

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The method employed by Dr. Hutton consists in placing a bar above the first figure after the change takes place: this is inadmis-sible, because it gives no notice of the change in the succeeding logarithms: the same objection applies to those tables in which a star is prefixed to the logarithm next to that in which the change occurs. In the logarithmic tables of Vega the star is used, but it is continued before the fourth figure of each succeeding logarithm to the end of the line. There is no objection to this in point of principle, and the only inconvenience which attends it, is that it increases the breadth of the page, a circumstance which could not be admitted in the present tables, without sacrificing the column for converting sexagesimal arcs into seconds.

The utility of this latter part of the table was so sensibly felt, that the plan of employing a figure of about half the usual size was preferred, and by continuing the same type to the end of the line in which the change in the third figure had occurred, the principle which has been laid down was adhered to, and sufficient space was preserved for the column alluded to. It will be observed, that these small figures do not stand precisely in the middle of the space alloted to them; there are two reasons for this deviation: the proximity of a small figure to a larger one makes the difference of the two types more conspicuous, and the white vertical line preceding each logarithm is rendered more apparent by the space which thus occurs on the left side of every figure after the change has taken place.

By the adoption of this small figure, another advantage has been gained; the pages are now divided at every fifth line by a blank space, which enables the reader more easily to catch any logarithm he may be seeking. It is usual in many tables to mark these intervals by rules instead of spaces; neither of these methods appear to possess any very decided advantages over the other. They may, however, be employed in conjunction, and the result is a greater degree of distinctness than arises from the use of either separately. If a rule is placed at intervals of ten lines, and if these tens are subdivided by blank spaces into periods of five lines, the form of the table will be considerably improved. The reason which has induced me not to adopt this improvement in the present tables, is to be found in the difficulty of its typographical execution. When two rules, a vertical and an horizontal one, intersect each other, one of them must be cut

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that whenever this occurs the two printed lines never appear to cross each other, but a small break is left at the intersection; this may be noticed either at the top or bottom of the page, in the continuation of the lines which separate the five first columns from the five last of the logarithms. In consequence of this difficulty the rules between every tenth line have been omitted, and the space left is sufficient to admit of a line being drawn with ink at those intervals, a plan which I have adopted in my own copy, and which I should recommend to all who have frequent occasion for the use of these tables.

8th. Whenever additional information can be communicated in a table without increasing its bulk, or adding much to its expense, it ought always to be given; unless it is of such nature as to distract the attention too much from the part most frequently used. In compliance with this principle, it was my wish to mark those terminal figures of the logarithms which had been made true to the nearest unit by some peculiarity which, whilst it should not render them conspicu-ous, should yet distinguish them sufficiently whenever such accuracy should be desirable. A simple dot attached to a letter affords the smallest visible appendage, and I had at first proposed to place a dot over each letter, which had been increased by a unit: this position was, however, given up on further consideration, because the same sign has in some cases been employed to denote recurring decimals. Its position was therefore changed, and those figures which have been increased are distinguished by a dot immediately below them.

At the left side of each page of the logarithmic table, and sepa-rated from it by a broad dark line, are placed the degrees, minutes, and seconds corresponding to the natural numbers adjacent. The utility of this addition is so great, and its employment so frequent, that it was thought desirable to add it even at a considerable in-crease of expense. The circumstance of this table being arranged in pages of fifty lines each, a plan which was required by other rea-sons, has caused the whole degrees and minutes not to terminate at the bottom of each page. This inconvenience was considered of less importance than those which would have arisen from employing a page of sixty lines. If, however, any error should be feared from overlooking the change of the minutes in the first column, or of the degrees in the second, which may occur in the middle of a page, it may be pointed out by drawing a line in red ink under the figure

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ink at similar places in the second.

In order to prevent the inconvenience of the tables of arcs catch-ing the eye of persons only uscatch-ing the logarithms, it has been put in different and much smaller type, and has been completely separated from the page by a broad dark line.

9th. The different tables in a volume ought to be distinguished from each other by the art of the printer, in such a manner that any one may, from its peculiarity, be readily distinguished in turning the pages over rapidly. This may be accomplished—by enclosing some of them with rules—by putting broad borders of various kinds at the tops and sides of others—or by having them printed in a different coloured ink.

Every table ought to have a running title at the top expressed as concisely as possible, and when the formula by which it is constructed is simple, it would be advantageous to give it on each page.

There are some causes of indistinctness in tables which arise from other sources. It frequently happens, that

10th. The impression of the figures on one page is reversed on the opposite: this sometimes arises from the volume having been bound before the ink was quite dry, a fault which should be most carefully avoided. It is, however, more frequently caused by the bad quality of the ink employed by the printer.

Another defect arises when

11th. The transparency of the paper admits the figures on the reverse side to appear through.

In order to try whether

12th. Coloured paper is more favourable to distinctness than white, I had a page set up, and printed on paper of various colours and shades: almost all those whom I consulted agreed with me in giv-ing the preference to the coloured papers, but the particular tint was not so unanimously fixed upon. Yellow appeared to have the prefer-ence, and it is that which I have chosen for the first impression. The tint is at first considerably too deep, but it fades on exposure to the light: I should therefore recommend, that previously to binding this volume the sheets should be exposed for several days to the action of the sun.

It is not probable that the colour first selected should be found the best; we must wait the result of time and experience to determine

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different colours; and it is not improbable, that a tint which is least fatiguing to the eye when used by candle-light, may not be the best adapted to calculations by day-light.

I have now stated those circumstances which have been attended to for the purpose of rendering the present tables distinct; and I have also mentioned the precautions employed for making them accurate, It is not to be presumed that they are yet free from error; but in order to render them so as soon as possible they have been stereotyped, and a small number of impressions have been printed: by these means, whenever any error is detected, it will be corrected in the plate, and, a list of such errata being given, the earlier copies may be corrected by it.

CHARLES BABBAGE.

Devonshire Street, Portland Place, Jan. 20, 1827. ERRATA. Numbers. Logarithms. 24626 . . . for 3940 read 3939 44160 . . . 0201 . . . . 0291 51880 . . . 0000 . . . . 7150000 85289 . . . 8920 . . . . 8930 98213 . . . 1689 . . . . 1690 102767 . . . 5568 . . . . 5368 107638 . . . 6552 . . . . 6562 In the Differences. Diff. No. 315 9 for 224 read 284

68 At the bottom of the page the proportional parts are omitted, and should be supplied from the top of the next page.

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OF THE USE OF THE TABLES OF LOGARITHMS.

The logarithms given in the tables are all supposed to be positive, and to have the decimal point prefixed to them.

The index of a logarithm is the whole number preceding the dec-imal point; it may be positive or negative, and must be supplied according to the following rules:—

The index of the logarithm of any number greater than unity, is equal to one less than the number of figures on the left hand of the decimal point; thus the index of the logarithm of 3652 is 3·.

The index of any decimal fraction is a negative number, equal to unity added to the number of zeros immediately following the decimal point; thus the index of the logarithm of ·00462 is −3·; the

index of ·462 is −1·.6

Instead of employing negative indices, their complements to 10 are sometimes used, and +7· and +9· are substituted for the above indices −3· and −1· When this is done, it is necessary to reject, at some subsequent stage, the 10 by which the indices have thus been augmented.

Problem I

To find the logarithm of a given number.

Case 1.—If the number given consists of less than four figures, its logarithm will be found opposite to the number in one of the first five pages of the table.

Let the number whose logarithm is sought be 462. In the second page of the table, and in the fifth column opposite 462 will be found the decimal part of its logarithm, which is ·6646420; to this must be prefixed its index 2, and the logarithm of 462 is 2·6646420.

6

As the decimal part of the logarithm is not negative, it is better to put the negative sign of the index above, instead of before it, as 3· instead of −3·.

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If the given number consists of five figures, the four first figures will be found in the column marked Numbers, and the fifth on the line of large figures at the top of the page. The three first figures of the logarithm will be found in the column next to that of the four first figures, either in the same line with it, or, if there are no figures on that line, they are the first which occur above it. In case the first of the four remaining figures of the logarithm should be a small character, the three first figures will be found one line below that in which the four first figures of the number occur. The four other figures will be found in the intersection of the column at the head of which the last figure of the number is found, with the horizontal line in which the first four figures of the number occur.

Required the logarithm of 31274?

In the column adjacent to the number 3127 will be found 495, which are the three first figures of the decimal part of the logarithm. In the intersection of the vertical column, headed 4, with the horizontal line 3127, are found the figures 1834; these are the four last figures of the decimal part of the logarithm of 31274. Since it consists of five figures, the index of its logarithm is 4, and the logarithm of 31274 is 4·4951834.

Required the logarithm of 296·51?

On the same line as the figures 2965, and in the next column, the three first figures 472 of the decimal part of the logarithm are found, and in the same line of the vertical column, headed 1, are the remaining four 0393. Prefixing the proper index 2, the logarithm of 296·51 is 2·4720393.

Problem III.

To find the logarithm of a number consisting of six or seven fig-ures.

Find the logarithm of the five first figures by the last problem, and carrying the eye on to the last column headed Diff., look up that column until you see a difference printed in the same type as the logarithms, and its proportional parts in a smaller character. This difference is that which belongs to the logarithm just found. It consists of a small table of nine lines: out of this table must be taken

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is sought, which must be added to the logarithm of the first five figures. Opposite the seventh figure of the given number, and in the same table, another number will be found, the tenth part of which must be added to the last sum.

Ex.—What is the logarithm of 114·1285?

The log. of 114·12 is by the last problem . . . 2 · 0573618.

Opposite 8 (in the diff. 381 which is nearest above) 305

Opposite 5 in the same table 191 . . . 19·1

2·0573942 which is the logarithm of 114·1285.

N.B.—In the early part of the table of logarithms, the size of the page would not admit of the proportional parts corresponding to every difference being printed; the alternate ones were therefore omitted, although the places at which they commence are indicated. It can very rarely happen that any inaccuracy will result from this omission.

Problem IV.

To find the number corresponding to a given logarithm.

In the first column of logarithms, headed 0, find the three first figures of the decimal part of the given logarithm.

In this line, or in one of those immediately following, a logarithm will be found which is either exactly equal to the given one, or a little less than it.

On the same line with the logarithm so found, and in the column headed Numbers, the four first figures of the number corresponding to it will be found, and the fifth figure of that number will be seen at the top of the column in which the logarithm was found.

In order to find the sixth and seventh figures of the number:— Subtract the logarithm so found from the given logarithm; then in the small table of differences in the column at the side marked Diff., and which is next above the logarithm found, some number in its second column will occur either equal to the difference of the given logarithm, and that which was found in the table, or else next less than it. In either case the figure in the first column of the small table opposite this number will be the sixth figure of the number to be found.

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taken from the small table from the difference of the two logarithms, and adding a zero to the remainder, the number nearest to it in the same small table will be opposite to a figure which is equal to the seventh figure of the number whose logarithm was given.

Ex. 1.— Required the number corresponding to the logarithm 3·8799155?

On turning over the table, the three first figures ·879 of the given logarithm will be found opposite the number 7569; a little farther down the same column, opposite 7584, the four last figures of the logarithm occur in the column headed 3. And since the index of the given logarithm is 3, there must be four places of whole numbers. The number corresponding to the logarithm 3·8799155 is therefore 7584·3.

Ex. 2.—Required the number whose logarithm is 2·8650264? The nearest logarithm less than this in the table ·8650210, the number corresponding to which is 73286.

The nearest difference above is 59, and in the small table, headed 59, the nearest number less than 54 is 53, corresponding to the num-ber 9; this subtracted from 54 leaves unity, which multiplied by 10 produces 10, the nearest number to which in the small table is 12, which is opposite 2. And since the index is 2, there must be three places of whole numbers. The whole process stands thus:—

2·8650264 given logarithm.

73286... 8650210 nearest less.

.. 54 difference.

9 . . . 53 opp. 9 in small table, headed 59. ...

... ... ...

. 10

2 . . . 12 opp. 2 in small table. 732·8692

Problem V.

To multiply together several numbers.

Add together the logarithms of the respective numbers, and their sum will be the logarithm of their product.

Ex. 1.—Required the product of 2305 by 1·46?

log. of 2305 . . . 3·3626709

log. of 1.46 . . . ·1643529.

3·5270238. = log. of 3365·3. xiv

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log. 73·04 . . . .1·8635608. log. 7·291 . . . . ·8627871. log. 7·2312 . . . ·8592104. log. 25·925 . . . . 1·4137188. 4·9992771. 2741 log. of 99833 30 ... 31 . . . 7. 99833·7. Problem VI.

To divide one number by another.

Subtract the logarithm of the divisor from that of the dividend, the result is the logarithm of the quotient.

Ex.—Divide 12·6740 by 8·291. log. 12·6740 . . . 1·1029137 log. 8·291 . . . ·9186069 ·1843068 log. of 15286 . . . ·1842939.... .. 129 5 142 quotient 1·52865. Problem VII.

To find any power of a given number.

Multiply the logarithm of the given number by the exponent of the power, the product is the logarithm of that power.

Ex. 1.—Required the square of 3·1416?

its logarithm is . . . ·4971509.

the exponent of the req. power . . . 2

·9943018. 9·8696 . . . .... 2996. .. 22 5 . . . 22 9·86965 xv

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its logarithm . . . 1·6395861. the exponent . . . 5 2·1979305. 15773... 9143 .. 162. 6. . . 165 ·0157736.

It will be noticed, that in the last example the negative index −1 being multiplied by 5 produced −5, to which was added the number 3, carried from the decimal part, which is always positive.

If the complement 9 to the index −1 had been employed, the resulting index would have been 8, which is itself the complement of −2.

Problem VIII.

To find any root of a given number.

Divide the logarithm of a the given number by the index of the root, the quotient is the logarithm of the root required.

Ex. 1.—What is the square root of 3.141592? 2) its log. 0·4971498. ·2485749 1·7724... 5617 .. 132 5 123 ... ... ... ... . 90 4 98 1·772454 root.

Ex. 2.—Required the 4th root of .434296? 4) its log. 1·6377858 1·9094464 4437 81179 27 ... 27 5 ·811795 the root. xvi

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were added to it, to render it divisible, and the 3 thus borrowed were reckoned as tens, and added to the first figure of the logarithm, making 36.

Of the use of the two first columns of degrees, minutes, and seconds.

Problem IX.

To find the number of seconds in any given number of degrees, minutes, and seconds.

If the number of degrees is greater than 30, subtract 30◦ from

them as many times as may be necessary to reduce the remainder below that number.

1. If this remainder is less than 2◦ 4640′′, it will be found in

the first column of the table; and the number of seconds in it is the natural number opposite it in the column of numbers.

If the remainder is greater than 2◦ 4640′′, it will be found in the

second column, to within 10′′. The natural number in the same line,

with it multiplied by ten, must be taken, and the remaining units and decimal parts of the seconds in the given arc must be added to it.

2. For every 30◦ subtracted from the given number add 108000,

and the sum is the number of seconds in the given arc.

Ex. 1—Required the number of seconds in 2◦ 651′′?

The natural number opposite this arc in the table is 7611, which is the number of seconds contained in the given arc; its logarithm is 3·8814417.

Ex. 2—Required the number of seconds in 21◦ 1331′′

·2?

The number in the tables opposite the arc 21◦ 1330′′ is 7641,

which multiplied by ten, and the units and decimal parts of the seconds of the given arc being added, gives

76410 1·2 76411·2

The logarithm of this may be found in the same line. 76411 . . . ·8831559.

·2 . . . 11

4·8831570. xvii

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Given any number of seconds, to find the corresponding arc in degrees, minutes, and seconds.

Subtract 108000 from the given number, until the remainder is less than that number.

If this remainder is less than 10000 the degrees, minutes, and seconds will be found in the first column of arcs. These added to

the decimal parts, and 30◦ for each 108000 subtracted, give the arc

sought.

If the remainder is greater than 10000, omit the units and decimal parts, and find the arc corresponding to the four first figures in the second column of arcs. This added to the units and decimal parts,

and to 30◦ for each 108000 subtracted, will give the arc sought.

Ex.—What is the number of degrees, minutes, and seconds in

109121·4′′

subtract 108000

1121·4′′

Opposite 1121, in the first column of arcs, is 0◦ 1841′′, add the

decimal part ·4 and also 30◦, on account of the subtraction, and we

have

30◦ 1841′′

·4

for the degrees, minutes, and seconds contained in 109121·4′′

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1′′ 51′′ 141′′ 231′′ 321′′ 1 0000000 51 7075702. 101 0043214. 151 1789769 201 3031961. 2 3010300. 52 7160033 102 0086002. 152 1818436. 202 3053514. 3 4771213. 53 7242759. 103 0128372 153 1846914 203 3074960 4 6020600. 54 7323938. 104 0170333 154 1875207 204 3096302. 5 6989700 55 7403627. 105 0211893. 155 1903317. 205 3117539. 6 7781513. 56 7481880 106 0253059. 156 1931246. 206 3138672 7 8450980 57 7558749. 107 0293838. 157 1958997. 207 3159703 8 9030900. 58 7634280. 108 0334238. 158 1986571. 208 3180633 9 9542425 59 7708520 109 0374265. 159 2013971 209 3201463. ′′ 1010 0000000 ′

1

60 7781513. 50′′ 110 0413927. ′′ 40160 2041200. ′′ 30210 3222193. 11 0413927. 61 7853298 111 0453230. 161 2068259. 211 3242825. 12 0791812 62 7923917. 112 0492180 162 2095150 212 3263359. 13 1139434. 63 7993405 113 0530784 163 2121876 213 3283796 14 1461280 64 8061800. 114 0569049. 164 2148438 214 3304138. 15 1760913. 65 8129134. 115 0606978 165 2174839 215 3324385. 16 2041200. 66 8195439 116 0644580. 166 2201081. 216 3344538. 17 2304489 67 8260748 117 0681859. 167 2227165. 217 3364597 18 2552725 68 8325089 118 0718820 168 2253093. 218 3384565. 19 2787536 69 8388491. 119 0755470. 169 2278867 219 3404441 ′′ 2020 3010300. ′′ 10 70 8450980 ′

2

120 0791812 50′′ 170 2304489 ′′ 40220 3424227. 21 3222193. 71 8512583 121 0827854. 171 2329961 221 3443923. 22 3424227. 72 8573325. 122 0863598 172 2355284 222 3463530. 23 3617278 73 8633229. 123 0899051 173 2380461 223 3483049. 24 3802112 74 8692317 124 0934217. 174 2405492 224 3502480 25 3979400 75 8750613. 125 0969100 175 2430380 225 3521825 26 4149733 76 8808136. 126 1003705 176 2455127. 226 3541084 27 4313638. 77 8864907 127 1038037 177 2479733. 227 3560259. 28 4471580 78 8920946 128 1072100. 178 2504200 228 3579348 29 4623980. 79 8976271. 129 1105897 179 2528530 229 3598355. ′′ 3030 4771213. ′′ 20 80 9030900. ′′ 10130 1139434. ′

3

180 2552725 50′′ 230 3617278 31 4913617. 81 9084850 131 1172713. 181 2576786. 231 3636120. 32 5051500. 82 9138139. 132 1205739 182 2600714. 232 3654880. 33 5185139 83 9190781. 133 1238516 183 2624511. 233 3673559 34 5314789 84 9242793. 134 1271048. 184 2648178 234 3692159. 35 5440680 85 9294189 135 1303338. 185 2671717 235 3710679. 36 5563025 86 9344985. 136 1335389 186 2695129 236 3729120 37 5682017 87 9395193. 137 1367206. 187 2718416 237 3747483 38 5797836. 88 9444827. 138 1398791. 188 2741578 238 3765770. 39 5910646 89 9493900 139 1430148 189 2764618 239 3783979 ′′ 4040 6020600. ′′ 30 90 9542425 ′′ 20140 1461280 ′′ 10190 2787536 ′

4

240 3802112 41 6127839. 91 9590414. 141 1492191 191 2810334. 241 3820170 42 6232493. 92 9637878 142 1522883 192 2833012 242 3838154. 43 6334685. 93 9684829 143 1553360 193 2855573 243 3856063. 44 6434527. 94 9731279. 144 1583625. 194 2878017 244 3873898 45 6532125 95 9777236 145 1613680 195 2900346 245 3891661. 46 6627578 96 9822712 146 1643529. 196 2922561. 246 3909351 47 6720979. 97 9867717 147 1673173 197 2944662 247 3926970. 48 6812412 98 9912261. 148 1702617 198 2966652. 248 3944517. 49 6901961. 99 9956352. 149 1731863. 199 2988531. 249 3961993 ′′ 5050 6989700 ′′ 40100 0000000 ′′ 30150 1760913. ′′ 20200 3010300. ′′ 10250 3979400

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4′ 11′′ 51′′ 551′′ 641′′ 731′′ 251 3996737 301 4785665. 351 5453071 401 6031444. 451 6541765 252 4014005 302 4800069 352 5465427. 402 6042261. 452 6551384 253 4031205 303 4814426 353 5477747 403 6053050 453 6560982 254 4048337 304 4828736. 354 5490033. 404 6063814. 454 6570559. 255 4065402. 305 4842998 355 5502284. 405 6074550 455 6580114. 256 4082400. 306 4857214 356 5514500. 406 6085260 456 6589648 257 4099331 307 4871384. 357 5526682 407 6095944 457 6599162 258 4116197 308 4885507 358 5538830 408 6106602. 458 6608655. 259 4132998. 309 4899585. 359 5550944 409 6117233 459 6618127. ′′ 20260 4149733 ′′ 10310 4913617. ′

6

360 5563025 50′′ 410 6127839. ′′ 40460 6627578 261 4166405 311 4927604. 361 5575072 411 6138418 461 6637009 262 4183013. 312 4941546. 362 5587086. 412 6148972 462 6646420. 263 4199557 313 4955443 363 5599066 413 6159501. 463 6655810. 264 4216039 314 4969296 364 5611014. 414 6170003 464 6665180. 265 4232459. 315 4983106. 365 5622929. 415 6180481. 465 6674530. 266 4248816 316 4996871. 366 5634811. 416 6190933 466 6683859 267 4265113. 317 5010593. 367 5646661. 417 6201361. 467 6693169. 268 4281348. 318 5024271 368 5658478 418 6211763. 468 6702459. 269 4297523. 319 5037907. 369 5670264. 419 6222140 469 6711728 ′′ 30270 4313638. ′′ 20320 5051500. ′′ 10370 5682017 ′

7

420 6232493. 50′′ 470 6720979. 271 4329693. 321 5065050 371 5693739 421 6242821. 471 6730209 272 4345689 322 5078559. 372 5705429 422 6253125. 472 6739420. 273 4361626 323 5092025 373 5717088 423 6263404. 473 6748611 274 4377506. 324 5105450 374 5728716 424 6273659. 474 6757783 275 4393327. 325 5118834. 375 5740313. 425 6283889 475 6766936 276 4409091. 326 5132176 376 5751878 426 6294096. 476 6776070. 277 4424798. 327 5145478. 377 5763414. 427 6304279. 477 6785184. 278 4440448. 328 5158738 378 5774918. 428 6314438. 478 6794279. 279 4456042 329 5171959. 379 5786392 429 6324573. 479 6803355 ′′ 40280 4471580 ′′ 30330 5185139 ′′ 20380 5797836. ′′ 10430 6334685. ′

8

480 6812412 281 4487063 331 5198280. 381 5809250. 431 6344773. 481 6821451. 282 4502491 332 5211381. 382 5820634. 432 6354837 482 6830470 283 4517864 333 5224442 383 5831988. 433 6364879. 483 6839471 284 4533183 334 5237465. 384 5843312 434 6374897 484 6848454. 285 4548449. 335 5250448 385 5854607 435 6384893. 485 6857417 286 4563660 336 5263393. 386 5865873 436 6394865. 486 6866363. 287 4578819. 337 5276299 387 5877110. 437 6404814 487 6875290. 288 4593925. 338 5289167 388 5888317 438 6414741 488 6884198 289 4608978 339 5301997. 389 5899496 439 6424645 489 6893089. ′′ 50290 4623980. ′′ 40340 5314789 ′′ 30390 5910646 ′′ 20440 6434527. ′′ 10490 6901961. 291 4638930. 341 5327544. 391 5921768. 441 6444386. 491 6910815. 292 4653829. 342 5340261 392 5932861. 442 6454223. 492 6919651 293 4668676 343 5352941 393 5943926. 443 6464037 493 6928469 294 4683473 344 5365584 394 5954962 444 6473830. 494 6937269 295 4698220 345 5378191. 395 5965971. 445 6483600 495 6946052. 296 4712917 346 5390761. 396 5976952. 446 6493349. 496 6954817. 297 4727564 347 5403295. 397 5987905 447 6503075 497 6963564. 298 4742163. 348 5415792 398 5998831. 448 6512780 498 6972293 299 4756712. 349 5428254 399 6009729. 449 6522463 499 6981005 ′

5

300 4771213. 50′′ 350 5440680 ′′ 40400 6020600. ′′ 30450 6532125 ′′ 20500 6989700

(50)

8′ 21′′ 911′′ 101′′ 1051′′ 1141′′ 501 6998377 551 7411516. 601 7788745. 651 8135810. 701 8457180 502 7007037 552 7419391. 602 7795965. 652 8142476. 702 8463371 503 7015680. 553 7427251 603 7803173 653 8149132. 703 8469553 504 7024305 554 7435098. 604 7810369 654 8155777 704 8475727. 505 7032914. 555 7442930. 605 7817554. 655 8162413. 705 8481891 506 7041505 556 7450748. 606 7824726 656 8169038 706 8488047 507 7050080. 557 7458552. 607 7831887. 657 8175654. 707 8494194 508 7058637 558 7466342. 608 7839036. 658 8182259. 708 8500333. 509 7067178. 559 7474118 609 7846173. 659 8188854 709 8506462 ′′ 30510 7075702. ′′ 20560 7481880 ′′ 10610 7853298 ′

11

660 8195439 50′′ 710 8512583 511 7084209 561 7489629. 611 7860412 661 8202015. 711 8518696 512 7092700. 562 7497363 612 7867514 662 8208580. 712 8524800. 513 7101174. 563 7505084. 613 7874605. 663 8215135 713 8530895 514 7109631 564 7512791 614 7881684. 664 8221681. 714 8536982 515 7118072 565 7520484 615 7888751 665 8228216 715 8543060 516 7126497 566 7528164 616 7895807 666 8234742 716 8549130 517 7134905 567 7535831. 617 7902852. 667 8241258 717 8555192. 518 7143298. 568 7543483 618 7909885. 668 8247765. 718 8561244 519 7151674. 569 7551123. 619 7916906 669 8254261 719 8567289. ′′ 40520 7160033 ′′ 30570 7558749. ′′ 20620 7923917. ′′ 10670 8260748 ′

12

720 8573325. 521 7168377 571 7566361 621 7930916 671 8267225 721 8579353. 522 7176705 572 7573960 622 7937904. 672 8273693. 722 8585372. 523 7185017. 573 7581546 623 7944880 673 8280151. 723 8591383. 524 7193313. 574 7589119. 624 7951846. 674 8286599. 724 8597386. 525 7201593 575 7596678 625 7958800 675 8293038. 725 8603380 526 7209857 576 7604225. 626 7965743 676 8299467. 726 8609366 527 7218106 577 7611758 627 7972675 677 8305887. 727 8615344 528 7226339 578 7619278 628 7979596 678 8312297. 728 8621314. 529 7234557. 579 7626786. 629 7986506 679 8318698. 729 8627275 ′′ 50530 7242759. ′′ 40580 7634280. ′′ 30630 7993405 ′′ 20680 8325089 ′′ 10730 8633229. 531 7250945 581 7641761 631 8000294. 681 8331471 731 8639174. 532 7259116 582 7649230. 632 8007171. 682 8337844. 732 8645111. 533 7267272 583 7656686. 633 8014037 683 8344207 733 8651040. 534 7275413. 584 7664128 634 8020893. 684 8350561 734 8656961. 535 7283538. 585 7671559. 635 8027737 685 8356906. 735 8662873 536 7291648. 586 7678976 636 8034571 686 8363241 736 8668778 537 7299743. 587 7686381 637 8041394 687 8369567 737 8674675. 538 7307823. 588 7693773 638 8048207. 688 8375884 738 8680564. 539 7315888. 589 7701153. 639 8055009. 689 8382192 739 8686444 ′

9

540 7323938. 50′′ 590 7708520 ′′ 40640 8061800. ′′ 30690 8388491. ′′ 20740 8692317 541 7331973. 591 7715875. 641 8068580 691 8394780 741 8698182 542 7339993. 592 7723217 642 8075350 692 8401061. 742 8704039 543 7347998 593 7730547. 643 8082110. 693 8407332 743 8709888 544 7355989. 594 7737864 644 8088859. 694 8413595. 744 8715729 545 7363965 595 7745170. 645 8095597 695 8419848 745 8721563. 546 7371926 596 7752463. 646 8102325 696 8426092 746 8727388 547 7379873 597 7759743 647 8109043. 697 8432328. 747 8733206 548 7387806. 598 7767012. 648 8115750 698 8438554 748 8739016. 549 7395723 599 7774268 649 8122447. 699 8444772. 749 8744818 ′′ 10550 7403627. ′

10

600 7781513. ′′ 50650 8129134. ′′ 40700 8450980 ′′ 30750 8750613.

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