46* Intelligence and Miscellaneous Articles. 



A paper by A. De Morgan, Esq., of Trinity College, was read, 

 containing observations upon the principles which have usually been 

 referred to in treating of series and of the fundamental doctrines of 

 the differential calculus, several of which principles the author con- 

 ceives have been assumed without due proof; and examples were 

 given in which such principles are false. 



Professor Miller exhibited and explained the instrument invented 

 by M. Say, for the purpose of taking specific gravities, with some im- 

 provements of his own. 



Mr. Willis exhibited and explained an instrument constructed by 

 him, which produces correct representations of the orthographic pro- 

 jections of irregular objects, as, for instance, of bones : this he pro- 

 poses to call an Orthograph. 



Mr. W. VV. Fisher gave a statement of his views concerning the 

 origin of tubercular diseases; such diseases, he conceives, arise from 

 a deficiency of nutritive energy in the osseous system, and from the 

 modifications introduced by this deficiency into the character of other 

 vital processes in the animal ceconomy. 



LXX. Intelligence and Miscellaneous Articles. 



FURTHER REMARKS ON CHEMICAL SYMBOLS IN REPLY TO 

 MR. PHILLIPS. BY Mil. JOHN PRIDEAUX. 



IN your Number for this month (April, p. 246,) is a letter from Mr. 

 Phillips to Mr. Graham, a part of which is employed to show that my 

 remarks on his former censure of chemical symbols " are inaccurate 

 both with regard to the facts and fancies of symbolizing." (p. 248.) 

 A few words may be requisite to make it appear how far this has 

 been done with respect to the facts ; the fancies may shift for them- 

 selves. 



On the symbols for phosphoric acid and water he does not offer any 

 thing new. except that (p. 2.30, at foot,) he cannot discover the ad- 

 vantage of Aq over H : the ambiguity of the latter symbol having 

 been, hitherto, his principal objection. 



My objection to " the specimen" was not one of expression, with 

 which, having said so much on it before (Lond. andEdinb. Phil. Mag. 

 vol. x. p. 104), I should not have meddled, but of atomic consti- 

 tution, the proportions of oxygen in the different formulae being 

 quite at variance. Such mistakes were to be ascribed to misprint or 

 other inadvertence, and not to the symbols ; certainly not to Mr; 

 Phillips, particularly after his informing us (Lond. and Edinb. Phil. 

 Mag. vol. iii. p. 445), " the statements are taken from all the systems 

 I have been able to collect;" and further, that he had examined "ten 



svstems of notation, in order to discover the meaning of N a 2 H P. 

 ' It seems I have offended in taking up statements which he neither 

 made nor intended (p. 249); that his intention was to describe an 

 " imaginary compound, as to the constitution of which all should 

 agree." Yet the symbols were certainly exhibited as " specimens of 



