Elementary arithmetic, with brief notices of its history... by Robert Potts.

LOGARITHMS.

of the uses of the tables. A translation1 of this work2 was made into
English by Edward Wright, M.A., Fellow of Geonville and Caius
College, Cambridge, who died in 1615. The translation, however, was
published in 1618 by his son Samuel Wright (then a scholar of the
same college), and dedicated to the East India Company.
A preface to the reader was added by Henry Briggs, and " a table
to finde the part proportionall." Henry Briggs was educated at
St. John's College, Cambridge; admitted to the degree of AM.A. in
1585; elected Fellow in 1588, and appointed reader on Dr. Linacre's
foundation in 1592. In 1596 he was chosen the first reader in
Geometry in Gresham College, London, and afterwards, in 1619, he
was appointed the first Savilian professor of geometry at Oxford.
Soon after the publication of the " Canon Mirificus," Briggs communicated in his lectures at Gresham College the improvement of making
1 the logarithm of the ratio of 10 to 1, instead of 2-30258, as Napier
had done. And from the evidence that exists, it appears that he was
the first person who publicly made known the advantages of this
change in the scale, which he also communicated to Napier himself.
In a letter to Mr. (afterwards Archbishop) Usher, of the date of
10th March, 1615, he writes: " Napier, lord of Markinston, hath set
my head and hands at work with his new and admirable logarithms.
I hope to see him this summer, if it please God, for I never saw a book
which pleased me better and made me more wonder. I purpose to
discourse with him concerning eclipses, for what is there we may not
hope for at his hands." Accordingly he visited Napier in the summer
of 1615. Their first meeting was described to William Lilly, who has
thus recorded the account in his "Life and Times."
"I will acquaint you with one memorable story related unto me
by John MIarr, an excellent mathematician and geometrician, whom
I conceive you remember. He was servant to King James I. and
Charles I. At first, when the Lord Napier, or iMarchiston, made
public his logarithms, Mr. Briggs, then reader of the Astronomy
Lectures at Gresham College, in London, was so surprised with admiration of them, that he could have no quietness in himself until he had
seen that noble person the Lord Marchiston, whose only invention they
were. He acquaints John Marr herewith, who went into Scotland
1 The following "Admonition" does not appear in the original Latin, page 22,
sect. 9, cap. 4. It was most probably added by Napier himself when he revised
Wright's translation. It refers to that system of the logarithms of the natural
numbers in which 1 is made the logarithm of the ratio of 10 to 1. " An Admonition. But because the addition and subtraction of these former numbers may
seem somewhat painful, I intend (if it shall please God) in a second edition, to
set out such logarithms as shall make those numbers above written to fall upon
decimal numbers, such as 100,000,000, 200,000,000, 300,000,000, &c., which are
easie to be added or abated to or from any other number."
2 The complete title-page is:-"A description of the admirable Table of Logarithmes:-with a declaration of the most Plentifull, Easie, and Speedy use thereof
in both kinds of Trigonometry, as also in all Mathematical Calculations. Invented
and published in Latine by that Honourable Lord John Nepair, Baron of Marchiston,
and translated into English by the late learned and famous Mathematician, Edward
Wright. With an addition of the Instrumentall Table to finde the part Proportionall,
intended by the Translator, and described in the end of the Booke, by Henrie Brigs,
Geometry-reader at Gresham House in London. All perused and approved by the
Authour, and published since the death of the Translator. Whereunto is added
new Rules for the ease of the student. London, printed for Simon Waterson,
1618."