# Collins, John

, an eminent accomptant and mathematician, was the son of a nonconformist divine, and horn at Wood Eaton near Oxford in March 1624. At sixteen years of age he was put apprentice to a bookseller in Oxford; but soon left that trade, and was employed as clerk under Mr. John Mar, one of the clerks of the kitchen to prince Charles, afterwards Charles II. This Mar was eminent for his mathematical knowledge, and constructed those excellent dials with which the gardens of Charles I. were adorned: and under him Collins made no small progress in the mathematics. The intestine troubles increasing, he left that employment and went to sea, where he spent the greatest part of seven years in an English merchantman, which became a man of war in the Venetian service against the Turks. Here having leisure, he applied himself to merchants accompts, and some parts of the mathematics, for which he had a natural turn; and on coming home, he took to the profession of an accomptant, and composed several useful treatises upon practical subjects. In 1652 he published a work in folio, entitled “An Introduction to Merchants’ Accompts,” which was reprinted in 1665, “with an additional part, entitled” Supplements to accomptantship and arithmetic.“A part of this work, relating to interest, was reprinted in 1685, in a small 8vo volume In 1658 he published in 4to, a treatise called” The Sector on a Quadrant; containing the description and use of four several quadrants, each accommodated for the making of sun-dials, &c. with an appendix concerning reflected dialling, from a glass placed at any inclination.“In 1659, 4to, he published his” Geometrical dialling;“and also the same year, his” Mariner’s plain Scale new plained.“In the Philosophical Transactions of the Royal Society, of which he was now become a member, he fully explained and demonstrated the- rule given by the Jesuit De Billy, | for” finding the number of the Julian period for any year assigned, the cycles of the sun and moon, with the Roman indiction for the years being given.“To this he has added some very neatly-contrived rules for the ready finding on what day of the week any day of the month falls for ever; and other useful and necessary kalendar rules. In the same Transactions he has a curious dissertation concerning the resolution of equations in numbers. In No. 69 for March 1671, he has given a most elegant construction of that chorographical problem, namely:” The distances of three objects in the same plane, and the angles made at a fourth place in that plane, by observing each object, being given; to find the distances of those objects from the place of observation?“In 1680 he published a small treatise in 4to, entitled” A Plea for the bringing in of Irish cattle, and keeping out the fish caught by foreigners; together with an address to the members of parliament of the counties of Cornwall and Devon, about the advancement of tin, fishery, and divers manufactures.“In 1682 he published in 4to,” A discourse of Salt and Fishery;“and in the Philosophical Transactions, No. 159, for May 1684, is published a letter of his to Dr. JohnWallis, oh some defects in algebra. Besides these productions of his own, he was the chief promoter of many other valuable publications in his time. It is to him that the world is indebted for the publication of Barrow’s” Optical and geometrical lectures;“his abridgment of” Archimedes’s works,“and of” Apollonius’s Conies“Branker’s translation of” Rhonius’s Algebra, with Pell’s additions“” Kersey’s Algebra“Wallis’s History of Algebra” “Strode of Combinations” and many other excellent works, which were procured by his unwearied solicitations.

While Anthony earl of Shaftesbury was lord chancellor, he nominated Collins, in divers references concerning suits depending in chancery about intricate accounts, to assist in the stating thereof. From this time his talents were in request in other places, and by other persons; by which he acquired, says Wood, some wealth and much fame, and became accounted, in matters of that nature, the most useful and necessary person of his time; and in the latter part of his life, he was made accomptant to the royal fishery company. In 1682, after the act at Oxford was finished, he rode from thence to Malmesbury in Wiltshire, in order to view the ground to be cut for a river between the Isis | and the Avon; but drinking too freely of cyder, when over-heated, he fell into a consumption, of which he died Nov. 10, 1683. About twenty-five years after his death, all his papers and most of his books came into the hands of the learned and ingenious William Jones, esq. fellow of the Royal Society, and father to the more celebrated sir Wm. Jones; among which were found manuscripts upon mathematical subjects of Briggs, Oughtred, Pell, Scarborough, Barrow, and Newton, with a multitude of letters received from, and copies of letters sent to, many learned persons, particularly Pell, Wallis, Barrow, Newton, James Gregory, Flamstead, Towniey, Baker, Barker, Branker, Bernard, Slusius, Leibnitz, Ischirphaus, father Bertet, and others. From these papers it is evident, that Collins held a constant correspondence for many years with all the eminent mathematicians of his time, and spared neither pains nor cost to procure what was requisite to promote real science. Many of the late discoveries in physical knowledge, if not actually made, were yet brought about by his endeavours. Thus, in 1666, he had under consideration the manner of dividing the meridian line on the true nautical chart; a problem of the utmost consequence in navigation: and some time after he engaged Mercator, Gregory, Barrow, Newton, and Wallis, severally, to explain and find an easy practical method of doing it; which excited Leibnitz, Halley, Bernoulli, and all who had capacity to think upon, such a subject, to give their solutions of it: and by this means the practice of that most useful proposition is reduced to the greatest simplicity imaginable. He employed some of the same persons upon the shortening and facilitating the method of computations by logarithms, till at last that whole affair was completed by Halley. It was Collins who engaged all that were able to make any advances in the sciences, in a strict inquiry into the several parts of learning, for which each had a peculiar talent; and assisted them by shewing where the defect was in any useful branch of knowledge; by pointing out the difficulties attending such an inquiry; by setting forth the advantages of completing that subject; and lastly, by keeping up the spirit of research and improvement.

Collins was likewise the register of all the new improvements made in the mathematical science; the magazine,
to which all the curious had recourse; and the common
repository, where every part of useful knowledge was to
| be found. It was upon this account that the learned styled
him “the English Mersenus.” If some of his correspondents had not obliged him to conceal their communications,
there could have been no dispute about the priority of the
invention of a method of analysis, the honour of which evidently belongs to the great 0\ T ewton. This appears undeniably from the papers printed in the “Commercium epistolicuni D. Joannis Collins & aliorum de analysi promota
jussu societatis regiae in lucem editum, 17 12,” in 4to. ^{1}

^{1}

Biog. Brit. Ward’s Crcshum Professors. Martin’s Biog. Philos. Ath. Ox. vol. II.