II O O K E. 



109 



About the tame i ? contrived the circular 



pendulum, which was htwn to the Royal Socit 



i \ 



This pendulum, which is described in Hooke'* 

 madveraons on the Machina Crlestis ot docs 



not vibrate backwanU ami forward*, but always in a 

 eirde, - the string being suspended above at the tripe- 

 dal length. and the ball fixed below, as knppMe at the 

 end of the fly of a common jack. The motion of this 

 circular pendulum i* a* regular, and much the Mine 

 with thoe mentioned before ; and was made to give 

 warning at any moment of it* ciroraunrntian, either 

 when it bad turned but a quarter, a half, or any lever 

 or greater part of its circle. So that here you had no- 

 tice not only of a second. but of the mort minute port 

 of a second of time." See Derham's Artificial Clock- 

 maker, p. 97. 



The ettabiuhment of the Royal Society in 1660, af- 

 forded to Dr Hooke numerous opportunities of extend. 

 ing hi* reputation. He published in 1660, a small 

 tract on the ascent of water in tmall tube* by capillary 

 attraction, in which he shewed that the height of the 

 water was in a certain proportion to their bore*). A 

 debate arose on thi* uhject in the Royal Society in 

 April \Gt'>\ ; hut Hooke's replies were considered to 

 him so hi 



, and raised him so high in the estimation of 

 the Society, that in 166S he was appointed curator of 

 npirimatit* to that ihsringiaishsd body. He was also 

 one of the 96 person* who were declared membeis of 



Society, at a meetirg of the conncfl held May 

 COth. 1663, by virtoe of the power given them by the 

 charter for two months. He was admitted to the so- 

 ciety on the 3d of June, and was peculiarly mmpmrt 

 from all paruianls In the same year be took hi* de- 

 cre* e/ Mas*** of Art*, and the Repository of the Royal 



the White Gallery of Gresham College was 

 ' to his care. About this time he drew up a 

 the use of those who might have 

 occasion to visit Greenland or Iceland. Those which 



r .. ** ,'. p'.'!t ,',','.,' >",'-.', ". .'.' - rimn ' 'wmrntol 

 tpiriu*pprar;ia what *hape; what they say and d- 

 thing of that kind very remarkable, and of good ^nfi( . 

 In May 1664 he delivered the astronomical lecture at 

 Greabam Colls** for Dr Pope, who was absent fa 

 and in the seme year Sir John Cutler gave him 

 of /JO per annum, for reading a course of 

 cm lectures, under the direction of the Royal 

 Society. These lectures were afterward* pi.bsimsd fa 

 4to, fa 19J9, sjnder the title of Ltttimu CaWmbaw. 



for grinding optic glasses, were wholly omitted. Du 

 ring the recess of the Royal Society, on account of the 

 plague in 1665, he accompanied MrWilkins and other in- 

 genious authors into Surry, where they continued their 

 philosophical labours. In 1665, at one of the first n 

 mgs of the Royal Society, Dr Hooke produced a MTV 

 small quadrant fur observing t he min utes and seeon i 

 means of an arm moved with a screw along tin- limb ot' 

 the quadrant His explanation of the inflexion of a direct 

 into a curv ilineal motion, was read to the Society on the 

 93d May 1&6. 



On the 19th of September 1666, he laid before 

 the Royal Society a model for rebuilding the city of 

 London, which was destroyed by the great fire ; but 

 though his plan was not executed, he was appointed 

 one of the surveyor* under the act of parliament ; a si- 

 tuation in which he realised a considerable aura of mo- 

 ney, which was found after his death in a large iron 

 chest, that appeared to have been shut up for SO 

 years. The irritable temper of our author now in- 

 volved him in several quarrel*, in all of which he con- 

 ducted himself with impropriety. I n our life of Heve- 

 liu*. we have already given an account of his contro- 

 versy with that astronomer respecting the compara- 

 tive merits of plain and telescopic sights. In 1671, he 

 attacked Newton's theory of light and colours ; and in 

 ne had a. warm dispute with Mr Oldenburg, the 

 secretary to the Royal Society, in consequence of hi* pam- 

 phlet, entitled, " A Description of Helioscope*, and some 

 other Instruments, made by Robert Hooke," in which 

 be complains that Oldenburg had not done him ju-tice re- 

 specting bis ismntmn of pendulum watches. The dis- 

 pute temiitiated by a declaration of the Royal Society, 



Houke. 



Jt^y; 



the Royal 

 College ; to 



which sM added divert ayiscelawavoM discourses. On 

 the I Itb Janu... he Royal Society settled upon 



him a salary of i.to per annum for life, for hi* labours 

 u curator cd n per run. U ; and en the 0th of March of 

 the same year, he was ayyssnted to succeed DrDacres as 

 prnftamr of geometry in Grcaham College. In the year 

 1 665, Hooke published hi* " Micr^rqMm, or some phy. 



[ glasses, with obsst ations and enquiries' there- 

 upon.- All the figures fa this work were drawn with 

 hi* own hand, and many of them are a kind of stand- 

 ard representations, which have been copied by uc- 

 ceadinc authors. The best are those of the comma* 

 mile, lea, louse, gnat, and ant. A new edition of it 

 bbn viand description* appear* I in 1745, in 

 which the baroscope, the bygrescopc, and the engine 



who took the part of their secretary In 1076, he nub- 

 bshed hi* " Description of Helioscopes, and some other 

 Instruments," a work which contains many curious in- 

 vention*, some of which are described in anagrams. 

 Upon the death of Oldenburg in In", Hooke was ap- 

 pointed to the vacant office of secretary ; and while he 

 held that situation, be publuned between 167<) and 

 1681 the seven numbers of the Pkilotopkicat Colin- 

 OM, which have always been regarded as a part of 

 the Philosophical Transactions. 



t this time the natural imiisjhnim of hi* temper 



He claimed as his 



About 



own the inventions and discoveries of every t.ther 

 son ; and he became so reserved fa conununicatii 

 on labours to the public, that though he read hi Cutle- 

 rian lecturrs.and exhibited nt-v .1 i!, l!,-yal 



Society, yet he never left any account of them to be 

 entered in the registers. When the I'lim-ipi/i appeared 

 m I6H6, be bud claim to the discovery of the doctrine 

 of gravitation, a claim which was warmly resented by 

 Sir Isaac Newton. Hooke. no doubt, had the merit of 

 stating, that gravitation was the power w hich kept the 

 planets fa their orbits, and he even made some experi- 

 ments to determine the law by which it was regulated; 

 but what a vast interval is there between this conjecture, 

 happy as it i*, and the splendid discoveries of Newton ! 

 In the year 1>87 he Miffered a severe loss by the 

 death of his brother's daughter, Mrs Grace Hooke, 

 who had lived several years with him ; and the dirties* 

 of hi* mind was ttill farther increased by a Chancery 

 .-nit with Sir John Cutler respecting his salary. In 

 Archbishop Tillotson employed him in contriv- 

 ing the plan of the hospital near H ox ton, founded by 

 Robert Ash ; and out of gratitude for his services, that 

 ,uihed prelate obtained for him the degree of 

 M.D. When the Chancery suit with Sir John Cutler was 



