44 HEronT — 1884. 



Graham seems to have been the first to maintain that hydrogen existed 

 in these salts otherwise than as water of crystallisation. 



1847. — It was Gerhardt ' who first clearly stated that the three sub- 

 stances, hydric sulphate, hydro-potassic sulphate, and potassic sulphate, 

 stand to one another in the relations represented by the formula? H 2 S0 4 , 

 KHS0 4 K-oSOj- He called salts of the type K 2 S0 4 , which correspond 

 to acids formed by the direct combination of water with an 'anhydride,' 

 equisels ; while for acids and basic salts he used the old names, sur-sels 

 and sous-sels. 



TABLE I. 



In this table of the nomenclature of the oxides of carbon, it is seen that 

 the names carbonic oxide and carbonic acid, Kohlenoxyd and Kohlensaiire, 

 oxide de carbon and acide carbonique, have been solely used by English, 

 German, and French chemists for the two oxides of carbon from the time 

 of their identification until twenty years ago. In Miller's ' Elements of 

 Chemistry' we find the term carbonic acid used in the two first editions, 

 in the Liter editions the term carbonic anhydride is introduced. In 

 Fownes' Manual we find the term carbonic acid used from the fourth 

 edition to the ninth ; in the tenth and eleventh editions we find both the 

 terms carbonic dioxide and carbonic oxide applied to the higher oxide, 

 and the terms carbon monoxide and carbonous oxide applied to the 

 lower ; in the thirteenth edition we find the terms carbonic anhydride and 

 carbon dioxide applied to the higher, and carbonic oxide and carbon 

 monoxide applied to the lower. So that in different editions of the same 

 manual we have the term carbonic oxide first applied to the lower, then to 

 the higher, and again to the lower oxide. In Watts's Dictionary (1863) 

 the lower oxide is called carbonic oxide, the higher carbonic anhydride ; 

 in the first Supplement (1872) the lower oxide is called carbon monoxide 

 and carbonous oxide, the higher oxide carbon dioxide and carbonic anhydride. 

 In France and Germany the terms oxide de carbon and Kohlenoxyd, 

 acide carbonique and Kohlensaiire, have continued to be used almost 

 universally to the present day. Among English and American chemists 

 of the present day there is a diversity of practice : carbonic oxide and 

 carbon monoxide being most generally used for the lower oxide, and 

 carbonic acid, carbonic anhydride, and carbon or carbonic dioxide for the 

 higher. 



TABLE II. 



In the nomenclature of the oxides of nitrogen, we find the names oxide 

 azoienx and oxide azotique, applied to the first and second oxides of nitro- 

 gen by the French Committee in 1787, have been employed by many 

 chemists to the present day. In the first edition of Thomson's ' System 

 of Chemistry ' (1802) we find the terms nitrous and nitric oxide used ; in 

 a later edition (1817) he introduced the terms protoxide of azote and 

 deutoxide of azote, calling the third oxide hyponitrous acid, and the fourth 

 nitrous acid. In Brande's ' Manual ' (1819) we have the term nitrous acid 

 given to the third oxide, but most chemists adopted Thomson's nomen- 

 clature. In Berzelius (French edition, 1829) we find gas oxide nitreux, 

 gas oxide nitrique and acide nitreux for the three lower oxides, and the 

 term acide nitroso nitrique for the fourth. In Graham's ' Elements ' (1842) 



1 Journal de Pharmacie, vol. xii. p. 57. 



