456 Astronomical Society. 



of Sciences, that " by carefully dissolving superoxidized barytes in 

 nitric acid, and precipitating the barytes from it by sulphuric acid, 

 the excess of oxygen remains united with the former acid, which by 

 this means becomes oxygenized nitric acid." How soon M. The- 

 nard discovered that he had mistaken the nature of the compound 

 formed, we do not know ; but in the fourth edition of his Traite de 

 Ckimie, published in 1824, he says (vol. ii. p. 83), " Puisque les 

 acides donnent plus de stabilite a l'eau oxigenee, c'est sans doute en 

 se corabinant avec le peroxide d'hydrogene : du moins, dans l'etat 

 actuel de la chimie, la composition de ce peroxide rend toute autre 

 hypothese invraisemblable. A v la verite, cette opinion n'est pas 

 celle que j'avais adoptee d'abord: j'avais pense que 1'oxigene se 

 combinait avec les acides, et qu'il en resultait un grand nombre 

 de nouveaux acides oxigenees." As the result of further experi- 

 ments he concludes : " je compris et je reconnus bientot que ce qui 

 m'avait paru etre des acides oxigenees n'etait que l'eau oxigenee et 

 acidifiee." It is clear, therefore, even in the opinion of Thenard 

 himself, that no such compound as oxygenated nitric acid exists : 

 and it is singular that Mr. Reid should have stated that as a fact, 

 which had been six years at least exploded by its promulgator ; 

 more especially as there is not, that we know of, one work on the 

 subject of chemistry written during that period, which contains any 

 notice of the existence of such an acid. 



The circumstance which we have just pointed out, as well as the 

 numerous mistakes that have been previously detected, prove that 

 Mr. Reid is not sufficiently acquainted with the science which he 

 has undertaken to teach : and even when he appears to possess 

 some knowledge of facts, they are usually very loosely, imperfectly 

 and incorrectly stated. We might adduce numerous instances to 

 those already given in support of these charges, but we shall now 

 conclude, with adding, that the work is very inaccurately printed ; 

 for in the chapter which we have examined, there occur four typo- 

 graphical errors, only one of which has been corrected ; and we 

 have detected several in other parts of the work, that are not in- 

 cluded in the Errata. 



LXX. Proceedings of Learned Societies. 



ASTRONOMICAL SOCIETY. 



May 14. — r | "<HE following communications were read: — 



-*■ 1. On an appearance of divisions in the exterior 

 ring of Saturn.. By Captain Henry Kater, Vice-President and 

 Treasurer of the Royal Society. 



The observations which form the subject of this paper were made 

 in the years 1825 and 1826, and remained unpublished from a wish 

 on the part of the observer to witness the appearances again, — but 

 bad health and the uncertain state of the atmosphere in this coun- 

 try have hitherto prevented him. 



The planet Saturn has been much observed by Captain Kater, 



for 



