292 



NATURE 



17 an. 27, 1 88 1 



present provision for practical work is very inadequate, and the 

 number of students has largely increased, vifhile the required 

 money is not forthcoming. I have already received the following 

 donations, and shall gratefully acknowledge any further help : — 

 Mr. Charles Danvin, 5/. Sx. ; Mr. Ed.vard Dormer, 5/. ; Mr. T. 

 Newland Allen, 3/. 3^ ; Mr. William Fa-seridge, 2I. 2s. ; 

 Anjnymou;, 2/. ; Mr. Frank Dethridge, i/. is. ; Anonymous, 

 l/. ; Mr. G. Eves, l/. ; Mrs. Eves, i/. ; Mr. R. Wilkinson, 

 il. IS. ; Rev. C. T. Mayo, i/. is. ; sinaller subscriptions, 4/. 15^. 

 Any further particulars will be most willingly given. 

 Florence Eves, 

 .Science Student of Newnham College 

 Mitton House, Uxbridge, January 22 



Minerva Ornaments at Troy v. Net-Sinkers 



Not having seen the numbers of Nature regularly during 

 the autumn, I did not observe Mr. .Sayce's reply to my letter on 

 the above subject until la'ely. I may perhaps trespass on your 

 space with a few lines in reference to it. 



I certainly did not observe any markings upon the stones in 

 question that could be construed into any likeness to a human 

 face or to that of an owl. Not having the opportunity of re- 

 examining them I must take this as granted according to Dr. 

 Scliliemann's judgment. Of course an expert can see, and see 

 with certainty, what to on*^ less experienced s';ems quite invisible. 

 At the same tiaie an enthusiast, as we all know, is rather apt to 

 *' oversee," and find in his relics more than actually exists. I 

 say this, as it is a common occurrence, and not in any way to 

 disparage Dr. Schliemann's valuable work. 



But admitting the existence of such outlines upon the stones in 

 question is it not far more probable that the half -savage natives of 

 the Troad miy have taken advantage of certain suggestive lines 

 and roughly outl nsd an image upon a net-sinker, than that they 

 made so large a number of rough and uncouth thmgs as likenesses 

 of Minerva? I he use of stones similarly chipped in the middle 

 as net-sinkers seems common to savages all over the world, and 

 it would seem t3 me therefore wiser to name them net-sinkers 

 (with outline-, &c.) than to ticket them " Minerva ornaments." 



One point, if I understand him aright, which Dr. Schliemann 

 endeavours to prove, is that Ancient Troy sto >d close to the 

 river. Hence the occurrence of net-sinkers may be considered 

 as probable. E. W. Claypole 



Antioch College, Yellow Springs, O., December 18, 1880 



THE PROVOST OF TRINITY 

 DUBLIN 



COLLEGE, 



TpHE Rev. Humphrey Lloyd, D.D., was born in 1800. 

 ■• He was the eldest son of the Rev. Bartholomew Lloyd, 

 who was Provost of Trinity College, Dublin, from 1 831 

 to 1837. Humphrey Lloyd entered his father's college in 

 1815, graduated as a Gold Medallist in Science in 1820, 

 and was elected a Fellow in 1824. In 1831 he was appointed 

 Professor of Natural Philosophy. He was co-opted a 

 .Senior Fellow in 1843, was made Vice- Provost in 1862, 

 and was appointed by warrant front the Crown to the 

 Provostship in 1867. He died, after a few days' illness, 

 in the Provost's house on the l6th inst. 



Full of years and honours, a very distinguished life 

 has been brought to a close. Part of it was spent in 

 laborious scientific research, part as the head of a great 

 teaching establishment. Both portions of his life were a 

 success, as even a short sketch of that life will show. 



Lloyd Wuis an excellent, though by no means a pro- 

 found, mathematician. On becoming the Professor of 

 Natural Philosophy he devoted himself with some ardour 

 to the study ot physical optics, and his report on this 

 subject, laid before the fourth meeting of the British 

 Association, was quite a masterpiece of reporting, and 

 may still be consulted with pleasure. He was not how- 

 ever by any means content with having a knowledge of 

 the work done by others, but w.%5 determined to enter on 

 the field of original work himself; an opportunity soon 

 offered. About 1832 Sir William Hamilton had been 

 investigating the relations between the surface of wave- 

 slowness and that of the wave, and therebv h:id been led 



to the discovery of some new geometrical properties of 

 the latter. These properties he demonstrated by means of 

 certain transformations of the equations of the wave- 

 surface, and he showed that this surface had fourconoidal 

 cusps at the extremities of the lines of single ray-velo:ity, 

 at ea^h of which the wave is touched not by two planes 

 as Fresnel supposed, but by an infinite number forming 

 a tangent cone of the second degree ; while, at the 

 extremities of the lines of siagle wave-velocity, there were 

 four circles of plane contact, in every point of each 

 of which the wave-surface is touched by a single plane. 

 These singular properties led Hamilton to anticipate two 

 new laws of refraction called by him external and internal 

 "conical refraction." Hamilton was naturally desirous 

 of having his theoretical conclusions proved by experi- 

 ment ; such experiments required a wonderful patience, 

 delicacy of tou^h, and an almost instinctive sagacity. As 

 possessing all these he selected Lloyd to solve his problem; 

 and by his labours in a short time the reality of this 

 interesting phenomenon was established. 



The msmoir by HaiTiilton and the experimental re- 

 searches by Lloyd appear in the saine voluine (xvii.) of 

 the Transactions of the Royal Irish Academy. 



Lloyd published several treatises and metnoirs relating 

 to optical science, but he was persuaded by Sir Edward 

 Sabine to turn his attention, about 1836, to the subject of 

 terrestrial magnetism. At his request the Board of 

 Trinity College, Dublin, built a magnetical observator}', 

 and the Professor entered with zaal upon those studies of 

 magnetism which will for ever rem lin connected with 

 his name. It would be unnecessary here to enumerate 

 his very numerous writings on this subject. 



In 1838 the British .Association resolved that having 

 regard to the high interest of the simultaneous magnetic 

 observations which have been for some time carried on in 

 Germany and various parts of Europe, and the important 

 results to which these have led, they regard it as highly 

 desirable that similar series of observations should be 

 instituted in various parts of the British Dominions, 

 and they suggested, as localities particularly important, 

 Canada, Ceylon, St. Helena, Vai Diemen's Land, and 

 the Cape of Good Hope, also in the Southern Hemi- 

 sphere. They further appointed as a Committee to 

 approach the Government on this question Sir J. Herschel 

 and Mr. Whewell, Dr. Peacock and Prof Lloyd. The 

 Coinmittee, appointed late in August, at once set about 

 their arduous work, and their memorial was laid before 

 Lord Melbourne in the November following. The Pre- 

 sident and Council of the Royal Society strongly supported 

 the memorial, and these concurrent representations were 

 attended with full effect. In the Report of the Com- 

 mittee to the British -Association in 1839 it is stated, 

 " probably at the very moment when this report will be 

 read, two ships, the Erebus and the Terror, under the 

 command of Sir James Clark Ross, will be already on 

 their voyage to the Antarctic Seas, carrying with them 

 every instrument requisite for the complete and effectual 

 prose :ution of important magnetical researches in the 

 high southern latitudes, and also complete establishments, 

 bo'th personal and instrumental, of the fived magnetical 

 observations to be placed at St. Helena, the Cape of 

 Good Hope, and Van Diemen's Land. It was no wonder 

 that the Committee were proud of the result of their 

 labours, and that they acknowledged in strong terms the 

 ample and liberal manner in which every demand on the 

 I national resources had been without exception granted, 

 expressing at the same time the hope that this splendid 

 example might be followed up by other nations. The 

 report is signed J. F. \V. Herschel and H. Lloyd. 



In 1843 Ur. Lloyd pointed out a mode of reducing the 

 error attending the determination of the intensity of the 

 earth's magnetic force to le=s than one-fifth of that by the 

 ordinary method. 



In 185S he again pointed out a fatal imperfection 



