121 



ROBINS, BENJAMIN. 



ROBINS, JOHN. 



J23 



Barnsdale and Sherwood after the fall of the Earl of Lancaster, and 

 remained there iu the first instance from about April 1322 to December 

 1323, when he entered tho service of Edward II., but tiring of the 

 constraints of a court life, at the end of a year returned to the woods 

 as described in the ballads. Mr. Hunter's disquisition is a very 

 curious one, and well deserves the perusal of those who may take an 

 interest in "bold Robin : " it forms No. IV. of his ' Critical and His- 

 torical Tracts ' (1852). The best as well as the most recent edition of 

 the ' Lytell Geste of Robin Hood,' and the other Robin Hood Ballads 

 is that of Mr. J. M. Gutch, 2 vols., Svo, 1847. 



ROBINS, BENJAMIN, a celebrated mathematician and artillerist, 

 was born at Bath, in 1707, of parents who were members of the Society 

 of Friends, and in such humble circumstances as to be unable to give 

 their son the benefits of a learned education. By the aid however of 

 some occasional instruction and a mind by nature formed to compre- 

 hend readily the processes of mathematical investigation, he early 

 attained to a considerable proficiency in the pure sciences ; and, as the 

 best means of beiug enabled to prosecute his favourite studies, he 

 determined to establish himself in London as a private teacher. Some 

 specimens of his skill in the solution of problems having been forwarded 

 to Dr. Femberton, that learned mathematician conceived so favourable 

 an opinion of his abilities as to encourage him in his design ; and 

 accordingly, about the year 1725, Mr. Robins came to town, in the garb 

 and professing the doctrines of a Quaker. The former, after a time, 

 he exchanged for the ordinary dress of the country. 



In the metropolis, and apparently in the intervals of leisure which 

 his employment as a teacher afforded, Mr. Robins applied himself to 

 the study of the modern languages, and diligently cultivated the 

 higher departments of science by reading the works of the ancient and 

 the best modern geometers ; these he appears to have mastered without 

 difficulty, and in 1727 he distinguished himself by writing a demon- 

 stration, which was inserted in the ' Philosophical Transactions ' for 

 that year, of the eleventh proposition in Newton's treatise on quadra- 

 tures. During the following year he published, in a work entitled 

 the ' Present State of the Republic of Letters,' a refutation of John 

 Bernoulli's treatise on the measure of the active forces of bodies in 

 motion, a subject which had been proposed as a prize question by the 

 Royal Academy of Sciences at Paris, and successfully answered by 

 Maclauriu. The foreign mathematician had endeavoured to support 

 the hypothesis of Leibnitz, that the forces are proportional to the 

 squares of the velocities which they produce, while both Maclaurin 

 and Robins were in favour of the original opinion of Descartes, that 

 the forces are proportional to the velocities simply. 



About this time Mr. Robins began to make those experiments for 

 determining the resistance of the air against military projectiles, 

 which have gained for him so much reputation. He is said also to 

 have directed the energies of his mind to the construction of mills, the 

 building of bridges, draining marshes, and making rivers navigable ; but 

 it does not appear that he was ever employed in carrying such works 

 into execution. The methods of fortifying places became a favourite 

 study with Mr. Robins, and, in company with some persons of distinc- 

 tion, probably his pupils, he made several excursions to Flanders, 

 where he had opportunities of examining on the ground the works of 

 the great masters in the art. 



In 1734, the celebrated Berkeley, bishop of Cloyne, author of the 

 ' Treatise on Human Knowledge,' published a small work called the 

 'Analyst,' in which, without intending to deny the accuracy of the 

 results, it is attempted to be shown that the principles of fluxions, as 

 they were delivered by Sir Isaac Newton, are not founded upon strictly 

 correct reasoning, inasmuch as it is assumed that the ratio between two 

 variable quantities may have a finite or infinite value when the quan- 

 tities are nascent or evanescent; that is, as the objector supposes, 

 when both quantities become zero. The objection is founded on a 

 misunderstanding of the subject, for by the term nascent or evanescent 

 is meant, not that each quantity is nothing, but that both are infinitely 

 small, or that they are less than anything assignable ; in which case 

 one of them may, notwithstanding, exceed the other in magnitude a 

 finite or even an infinite number of times. The talents of both 

 Maclaurin and Robins were employed in answering the objection ; 

 and for this purpose Robins published, in 1735, ' A Discourse concern- 

 ing the Certainty of Sir I. Newton's Method of Fluxions, and of 

 Prime and Ultimate Ratios.' It is easy to imagine however that great 

 difficulty would at first be felt in admitting a principle so different 

 from any which occurs in the ancient geometry ; and, before the sub- 

 ject was set at rest, Mr. Robins added to the first, two or three other 

 discourses explanatory of the calculus. 



In 1738 he wrote a defence of Newton against an objection on the 

 subject of the sun's parallax which occurs in a note at the end of 

 Baxter's ' Matho ;' and, in the following year, he published some 

 remarks on Euler's treatise of ' Motion,' on Smith's ' Optics,' and on 

 Dr. Jurin's discourse concerning vision. 



Mr. Robins's principal work, entitled ' New Principles of Gunnery,' 

 was published in 1742. To this is prefixed an account of the rise and 

 progress of modern fortification, and a history of the invention of gun- 

 powder, with a statement of the steps which had been taken towards 

 a knowledge of the theory of gunnery. Having then determined the 

 value of the explosive force of fired gunpowder and the effect of the 

 heat and moisture of the atmosphere on that force, he proceeds to 



describe the ballistic pendulum which he had invented, with the 

 manner of employing it in determining the velocities of shot when the 

 guns are charged with given quantities of powder ; and he treats at 

 length of the resistance of. the air on shot and shells during their flight, 

 a subject till then but little understood. This work had the honour 

 of being translated into German, and commented on by the learned 

 Euler. Some of the opinions advanced in it being questioned by the 

 author of a paper in the ' Philosophical Transactions,' Mr. Robins was 

 induced to reply to the objections, and to give several dissertations on 

 the experiments made by order of the Royal Society in 1746 and 

 1747 ; for these he was presented with the annual gold medal. A 

 number of experiments in gunnery subsequently made by Mr. Robins 

 were, after his death, published with the rest of his mathematical 

 works, by Dr. Wilson, and the collection, which makes two volumes 

 Svo, came out in 1761. 



Besides the pursuits of science, Robins appears to have been occa- 

 sionally occupied with subjects of a political nature. A convention 

 which had been made with the king of Spain, in 1738, respecting the 

 payment of certain claims made by British merchants in compensation 

 for the seizure of their ships and the destruction of their property by 

 the subjects of that monarch, not beiug considered satisfactory, the 

 opponents of the minister, Sir Robert Walpole, made it the ground of 

 an inquiry into his conduct, and Robins wrote three pamphlets on the 

 occasion. These gained for him considerable reputation, and a com- 

 mittee of the House of Commons being appointed to manage the 

 inquiry, he was chosen its secretary; he did not however hold the 

 post long, as a compromise took place between the opposing parties. 

 About ten years afterwards (1749) Mr. Robins wrote, as a preface to 

 the 'Report of the Proceedings of the Board of Officers on their 

 Inquiry into the Conduct of Sir John Cope,' an apology for the unsuc- 

 cessful issue of the action at Preston Pans in 1745. 



Great difference of opinion exists concerning the share which Mr. 

 Robins had in writing the account of Lord Anson's ' Voyage round 

 the World ' (1740-1744). The work was certainly commenced by the 

 Rev. W. Walter, the chaplain of the Centurion, who 'was in that ship 

 during the greater part of the voyage ; but, on the one hand, it is 

 said that the account of the reverend gentleman consisted chiefly of 

 matters taken verbatim from the journals of the naval officers ; and 

 that Robins, using the statement of courses, bearings, distances, &c. as 

 materials, composed the introduction and many of the dissertations in 

 the body of the work. On the other hand, we are told that Mr. Robins 

 was consulted only concerning the disposition of the plates, and that 

 he left England before the work was published. It is scarcely pro- 

 bable that a clergyman professing to write the history of such a voyage 

 should have merely copied a sailor's journal, and it may be reasonably 

 supposed that the greater part of the work as .it stood in the first 

 edition came from his pen ; while, with equal reason, it may be 

 allowed that Mr. Robins added the introduction and the scientific 

 notices. The first edition appeared in 1748, and four were disposed 

 of in the course of that year. 



Mr. Robins was offered iu 1749 his choice between two good appoint- 

 ments; the first, to go to Paris as one of the commissioners for 

 settling the boundaries of Acadia ; and the other, to be engineer in 

 general to the East India Company. He accepted the latter, and 

 departed iu December for Madras, where he arrived in July 1750. 

 His intentions were to put the fortifications in a good state of defence, 

 and he had actually prepared plans for the purpose when he was taken 

 ill with a fever. He recovered from this attack, but soon afterwards 

 fell into a declining state, and died on the 29th of July 1751, at the 

 age of forty-four years. 



He left behind him the character of being one of the most accurate 

 mathematicians of his age ; and the interest which he took in astronomy 

 may be inferred from his having availed himself of his interest with 

 Lord Anson to procure a new mural quadrant for the Royal Observa- 

 tory at Greenwich, and having taken with him to India a set of 

 instruments for the purpose of making observations in that country. 

 Dr. Button relates that in 1741 he was a competitor with Mr. Miiller 

 for the post of professor of fortification in the Royal Military Academy 

 at Woolwich ; and that the latter succeeded through some private 

 interest in obtaining the appointment. 



ROBINS, or ROBYNS, JOHN, an English astronomer and mathe- 

 matician, who was born in Staffordshire, about the close of the 15th 

 century or the beginning of the 16th, as it appears he was entered a 

 student at Oxford in 1516, and educated for the church. In manu- 

 script (Digby, 143) are preserved several iuedited tracts by Robins, 

 and from a note at the end it appears that he was of Merton College. 

 It seems that, in common with many others of that college, he devoted 

 himself to the study of the sciences, and he soon made such a progress, 

 says Wood, in ' the pleasant studies of mathematics and astrology, 

 that he became the ablest person in his time for those studies, not 

 excepting his friend Recorde,' whose learning was more general. 

 Having taken the degree of bachelor of divinity in the year 1531, he 

 was the year following made by King Henry VIII., to whom he was 

 chaplain, one of the canons of his college in Oxford. In December 

 1543 he was made a canon of Windsor, and afterwards one of the 

 chaplains to Queen Mary, who highly esteemed him for his learning. 

 He died on the 25th of August 1558, and was buried in the chapel of 

 St. George at Windsor. He left behind him several works in manu- 



