Royal Society, 227 



The total number of observations in Nos. V., VI., VII. are — 



No. V. . 



. . 59 9 



6 angles 



No. VI. . 



. . 99 4 



7 „ 



No. VII. . 



. . 80 15 



8 „ 



21 ;, 



The foregoing investigation warrants the belief that gall-stones 

 owe their geometrical forms to mutual pressure in the gall- 

 bladder and duct, and not to crystalline forces. 



[To be continued.] 



XXIX. Proceedings of Learned Societies. 



ROYAL SOCIETY. 



[Continued from p. 152.] 



May 3, 1866. — Lieut. -General Sabine, President, in the Chair. 



npHE following communication was read : — 

 X "The Calculus of Chemical Operations, being a Method for 

 the Investigation, by means of Symbols, of the Laws of the Distri- 

 bution of Weight in Chemical Change. — Part I. On the Construction, 

 of Chemical Symbols." By Sir R. C. Brodie, Bart., F.R.S. 



In chemical transformations the absolute weight of matter is un- 

 altered, and every chemical change, as regards weight, is a change 

 in its arrangement and distribution. Now this distribution of weight 

 is subject to numerical laws ; and the object of the present method 

 is to facilitate the study of these laws, by the aid of symbolic pro- 

 cesses. The data of the chemical calculus, as indeed of every other 

 application of symbols to the investigation of natural phenomena, 

 are supplied by observation and experiment ; and its aim is simply 

 to deduce from these data the various consequences which may be 

 inferred from them. The province of such a method commences 

 where that of experiment terminates. 



This part comprises the consideration of the fundamental princi- 

 ples of symbolic expression in chemistry, and also the application of 

 the method to the solution of perhaps the most important of all 

 chemical problems, namely, the question of the true composition, as 

 regards weight, of the units of chemical substances. 



Section I. In the first section certain definitions are given of those 

 weights, and relations of weight, of which the symbols are subse- 

 quently considered. It may be regarded as containing an analysis 

 of the subject of chemical investigation. The definitions are, of "a 

 chemical substance," "a weight," "a single weight," "a group of 



Q2 



