Royal Society. 143 



following a long train of analytical reasoning without so much as 

 seeing the symbols. A few essays and remarks on other subjects 

 are inserted, partly on account of their intrinsic merit, partly, we 

 suppose, with a view to exhibiting the extensive range of Mr. Ellis's 

 learning. We may particularize the following : — an essay " On 

 Roman Aqueducts," written for the purpose of determining the 

 amount of hydraulic knowledge exhibited in the arrangements made 

 for distributing the water, so far as they are known. " Some 

 Thoughts on Comparative Metrology " — an attempt to determine 

 historically the connexion between the measures of land used by dif- 

 ferent European nations. It would appear from internal evidence 

 that this essay could not have been composed before the end of 1 852. 

 If this circumstance is borne in mind, it may be justly thought that 

 the learning and out-of-the-way knowledge displayed in the course of 

 it render its composition one of the most remarkable instances on 

 record of mental powers continuing in unimpaired vigour in the 

 midst of bodily decay ; for Mr. Ellis's illness had now been going 

 on for more than three years. We may just name "Remarks on 

 certain Words in Diez's Etymological Dictionary of the Romance 

 Languages," and " Some Thoughts on the formation of a Chinese 

 Dictionary." The last article in the volume contains remarks " On 

 the Course of Mathematical Studies," being evidence laid before the 

 " Cambridge University Commission." Want of space forbids us to 

 make any remarks on this article, which suggests more questions 

 than one well worth discussion, and would well repay careful perusal. 



We must here close our notice of this mournful volume, the con- 

 tents of which we have attempted rather to describe than criticise. 

 Had we taken the latter course, it might have been necessary to 

 raise objections to some of Mr. Ellis's views. But of this there w r as 

 no need. The interest of the volume does not lie in its contents 

 Considered merely as matters of science, but rather as the memorial 

 of a singularly gifted man cut off before his promise ripened into 

 performance. The volume does not tell what the world has gained 

 by its author's life, but rather what it has lost by his death. 



We must add that Mr. Walton has discharged his duty as editor 

 very faithfully. So far as the printing, and the form and appearance 

 of the volume are concerned, there is little or nothing to be desired. 



XXVII. Proceedings of Learned Societies. 



ROYAL SOCIETY. 

 [Continued from p. 73.~\ 

 April 30, 1863. — Major-General Sabine, President, in the Chair. 

 HHHE following communications were read : — 

 -*■ " On Spectrum Analysis, with a Description of a large Spectro- 

 scope having nine Prisms, and Achromatic Telescopes of two feet 

 focal power." By John P. Gassiot, F.R.S. 



The author, after briefly alluding to the discoveries of Fox 

 Talbot, Wheatstone, Foucault, Kirchhoff, and Bunsen, and the im- 



