248 



NATURE 



Yjfan. 29, 1874 



Cliff and inventfng a method for drawing the meridian 

 line by the Pole star and finding the hour by the same ; 

 in 1703, on June 15, 16, and 18, he was making some 

 observations on spots on the sun ; and in 1706, on May 

 12, in conjunction with Flamstead at Greenwich, Captain 

 Stannyan at Berne, and Mr. Sharp at Bradford, he was 

 taking observations of the great solar eclipse of that day. 



From his various reports on these subjects it is clear 

 that Mr. Gray, while at Canterbury, had a good observa- 

 tory ; he had three telescopes, one of which was of i5ft., 

 an astronomical table, a theodolite, a pendulum clock, 

 and various other instruments, with the use of which he 

 was quite familiar ; but what his occupation was, other- 

 wise, there is no record. 



We now lose all sight of Gray until 171 7, when we find 

 him being recommended to the Charterhouse by Prince 

 George to become a pensioner there. The letter of re- 

 commendation is signed by the Prince, but says no more 

 than that the applicant is a proper person to receive the 

 advantage of residence. In 17 19 he entered the building 

 as a pensioner and remained there until his death, 

 seventeen years later. 



With his entrance into the Charterhouse a new career 

 of scientific research seemed to have opened itself to 

 Mr. Gray. He became an electrician, and, said Dr. 

 Richardson, his experiments led to such extraordinary 

 results that, but for them, electrical science might have 

 waited for centuries, or for ever, in the state in which he 

 found it. That the audience might know upon «hat 

 pre-existing daia Gray proceeded, I)r. Richardson traced 

 back the origin of experimental electricity to the reign of 

 Queen Elizabeth and to her physician, William Gilbert. 

 He reviewed from this source, briefly and succinctly, the 

 labours of Boyle, Otto de Guericke, Wall, Newton, ind 

 Hawksbee, introducing a model of Hawksbee's revolving 

 cylinder, and Sir Isaac's simple experiment of making 

 light bodies move bctw-ecn an excited plate of glass and a 

 table. 



In 1720 the first electrical work of Mr. Gray saw the 

 light in a paper entitled "An account of some new 

 electrical experiments," which appeared in that year in the 

 Philosophical Transactions. In this paper the com- 

 municability from one electrified substance to other 

 substances not previously electrified is described. 



From this point in Mr. Gfay's career Dr. Richardson 

 tracedhimstep by step throughhis experimental researches, 

 making each of his (Gray's) experiments a matter of 

 direct demonstration to the audience, and using only the 

 simple kind of instruments the original investigator 

 himself had at command. Thus were demonstrated the 

 experiments of the cork and the excited tube, the ivory 

 ball on the wooden rod, and the pack-thread experi- 

 ments, by which Gray discovered that electricity could 

 be conducted long distances. Next were demonstrate 

 the famous loop experiments and those with bridges 

 of pack-thread, silk, and wire, by which silk was 

 discovered to be an insulator, and the new fact of insu- 

 lation was recorded. The audience, at this point, were 

 carried, by description, to the Mansion of Mr. Gran- 

 ville Wheeler, Otterden House, near Faversham, and 

 were shown by a beautifully simple diagram, drawn for 

 the occasion by the distinguished George Cruikshank — 

 how Mr. Gray, putting up poles in Mr. Wheeler's grounds, 

 insulated a pack-thread line on silk supports, and on 

 July 14, 1729, sent by the line a communication through 

 a distance ot 650 ft. 



Another series of experiments showed how Mr. Gray 

 discovered induction, the conducting power of water and 

 of metals ; the fact that electricity arranges itself upon 

 the surfaces of bodies ; that attraction will take place in 

 vacuo ; and that an insulated, pointed iron rod, when 

 electrified by induction, will yield a brush at its extreme 

 point, will charge another insulated conductor, will give 

 a spark to the knuckle when tha is brought near, and 



will pass through a chain of animal bodies, if they be 

 insulated. 



A beautiful experiment with a soap-bubble, showing 

 how, when insulated and charged, it will attract, closed 

 the experimental part of the lecture. The experiments 

 throughout were highly successful, and were so rendered 

 as to be distinctly visible to all the observers. 



A few more points in the personal history of Gray 

 were introduced. It was told that he gained the 

 first Copley Medal of the Royal Society in 1731, and the 

 second in 1732, and that he uas admitted a Fellow of 

 the Society on March 15 of the latter year. A graphic 

 description was given of a meeting of the Royal Society on 

 November 25, 1731. At this meeting Prince George was 

 present with the Duke of Lorraine, and the Duke was 

 admitted a Fellow. Afterwards a model of a fire-engine, 

 used at York, was exhibited ; then Dr. Frobenius lec- 

 tured on phlogiston, and on the transmutation of phos- 

 phorus, using several pounds' worth of that now common 

 element. Finally, the company ascended to the library, 

 where Mr. Gray showed some experiments, proving how 

 electricity travels along conductors, and succeeded well, 

 notwithstanding the largeness of the company. 



Two remaining subjects relating to Gray were 

 briefly touched upon. One was his prediction that 

 what he was doing /// miniinis would some day be 

 so extended, that electrical phenomena would be 

 made to resemble those of thunder and lightning ; and 

 the other, his belief that he had invented what he 

 called a Planetarium, that is, a method of making a pith- 

 ball suspended by silk move in circles or ellipses round 

 a metallic centre set in a cake of resin, while the resin 

 was excited by friction of the hand. The first of these 

 observations of Gray had been fulfilled ; the latter had 

 appeared as an error of the last days of this wonderful 

 man, and might w-ell be forgiven. 



The death of Stephen Gray afforded the lecturer an 

 opportunity for a touching description of a man of science 

 struggling to the last with his labours. On February 

 ■4i 1735-36,116 was visited by Dr. Cromn^ell Mortimer, 

 the secretary of the Royal Society, who took from his 

 lips the account of the Planetarium by which, " if God 

 spared his life," the electrical philosopher would create, 

 he thought, much astonishment : but the following day, 

 experiment, speculation, and hope, lay alike low in death. 



NOTES 



The report which reached England a few days ago of the 

 death of Livingstone, and which Dr. Kirk was able to charac- 

 terise as possibly unfounded, as it closely resembled a discredited 

 one current in Zanzibar before he left, r-eceived important confir- 

 mation yesterday morning. We are enabled, however, to 

 state that a letter seems to have come from Lieut. Cameron at 

 Unyanyembe, reporting that a man named Chumas, who was 

 with Livingstone, had arrived there wi.th a circumstantial story 

 of his death, which Lieut. Cameron, with his slight knowledge^of 

 Suabili, had to turn into English. It now depends upon the 

 veracity of Chumas, of which at present there is no means of 

 judging. The circumstantiality is nothing, for the tale of the 

 lying Johanna man was quite as detailed. There is, however, 

 we are bound to confess, much reason to fear that we have lost 

 one of the most unselfish, noble, and devoted investigators the 

 century has produced. 



S^TllE Council of the Geological Society has awarded the 

 Wollaston Medal for the present year to Prof. Oswald Heer of 

 Zurich, and the balance of the Proceeds of the Wollaston Dona- 

 tion Fund to M. Henri Ngst of Brussels. The Murchison 

 Geological iMedal was awarded by the Council to Dr. Bigsby, 

 F.G.S., and the balance of the Proceeds of the Murchison 



