BRIGGS, HENRY, a celebrated mathematician, was born in 1556, at Warley wood, near Halifax, in the West riding of Yorkshire. At the age of 23 he left the gram mar school, and went to St John's College, Cambridge. In 1581 he took his degree of Bachelor of Arts. and three years afterwards, that of blaster; and in 1538 he was chosen a Fellow of that College. His passion for mathematical learning had already displayed itself in the progress of his studies, and such was the fame which he had acquired in this department, that in 1592 he was appointed examiner and lecturer in the mathematics ; and lie was soon after chosen reader of the physic lec tures, founded by Dr Linacre. Upon the establishment of Gresham College in London, Briggs was, in 1596, elected the first Professor of Geometry ; and in this new situation he drew up a table for determining the latitude of the place from the variation of the magnet. This ta ble was published by Dr Gilbert, in his book De Mag vete, and also by Thomas Blundeville, in his Thcoriques of the Seven Planets, a work which appeared in London in 1602. In the year 1609, he became acquainted with Mr James Usher, afterwards archbishop of Armagh, with whom he carried on a correspondence for many years, and two of these letters arc to be found in the published collection of Usher's letters.* About this time, in 1614, our countryman lord Napier, published his llfirci Logarithmorum canonis descriptio, containing an account of the discovery of logarithms. This work attracted the particular notice of Briggs, who appears to have perceived at an early period, the advantages of that change in the system of Napier, which was afterwards adopted. In the system invented by Na pier, the logarithms of a series of numbers, increasing in the decuple ratio of 1, 10, 100, formed a decreasing arithmetical series, in which the common difference of the terms was 2.3205851. Briggs, however, considered, that it would be more conformable to the decimal nota tion to adopt a system in which 1 should be the loga rithm of the ratio of 10 to 1. This alteration in the scale
of logarithms, was explained by Briggs in his lectures at Gresham College ; and he also communicated it by letter to lord Napier. Not satisfied with an epistolary correspondence, Briggs went to Scotland in 1616, for the express purpose of explaining to Napier the plan which he had formed. During their conversations on this subject, Napier observed, that the same plan had formerly occurred to him after he had calculated the logarithms according to his own system, and that he merely gave these to the world till his health and leisure should permit him to accommodate them to the new system. It was proposed by Briggs to make the loga rithms of the sines increase from 0, the logarithm of radius to infinity, while the sines themselves should de crease ; but Napier observes that it would be preferable to make them increase, so that 0 should be the logarithm of 1, and that 100000 should be the logarithm of radius. This suggestion met with the approbation of Briggs, who accommodated to it the numbers which he had al ready calculated ; and in 1617 he repeated his visit to Scotland to submit them to the consideration of his friend.f On his return to England in 1617, Briggs printed his Logarithmorum Chilias prima, though he does not seem to have published it till after the death of Na pier, which took place in 1618, as he expresses a hope that the causes which led to the change of the logarith mic system would be explained in the posthumous work of lord Napier. It would appear, however, that the Scotch mathematician preserved such a studied silence on the subject, as to create a suspicion that he wished himself to be considered as the sole author of the new system. Briggs was entitled to regard the conduct of his friend as injurious to his reputation, and he accord ingly asserted his claims to the improvement of Napier's system in the preface to his ?rithmetica Logarithmica, See.