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CHEMISTRY. 



MODERN CATAMARAN "TARANTELLA." 



CHEMISTRY. Chemical Philosophy. The sec- 

 ond report of the Committee of the British 

 Association on Chemical Nomenclature, made 

 to the Montreal meeting, contains tables show- 

 ing what different names the same substance 

 has received, and to what different substances 

 the same name has been given by the chemists 

 of different countries, and illustrating other 

 variations in nomenclature that have prevailed. 

 The report says that the usefulness of any sys- 

 tem of nomenclature depends on its perma- 

 nence. Curiously enough, the tables show that 

 where names have been adopted, supposed to 

 represent in some way the chemical constitu- 

 tion of bodies, they have not, as a rule, been 

 adhered to, the advance of knowledge necessi- 

 tating a change of opinion, while names which 

 took no account of such change of opinion have 

 endured. As a rule, those names are to be 

 preferred which have shown most vitality, and 

 have led to no ambiguity. "Where there are 

 two compounds composed of the same ele- 

 ments, the terminations " ous " and " ic " 

 should be employed. The prefixes "proto" 

 and " deuto," introduced by Thomas Thomson, 

 were intended to mark the compounds in a se- 



ries, not the number of atoms in a molecule. 

 Where retained, this use only should be made 

 of them. The conclusion of the report is in 

 favor of retaining names of substances in com- 

 mon use rather than to change them for names 

 indicating constitution, which might again be 

 found to require alteration in accordance with 

 some new view on the subject. 



The atomic theory has been set in a new 

 light by the researches of Mendelejeff and Lo- 

 thar Meyer, who, inquiring whether some 

 relations might not exist between the atom- 

 ic weights of the several elements and their 

 chemical and physical properties, succeeded in 

 tracing an apparent simple relation between 

 the atomic weights and the specific volumes of 

 a considerable number of them, which, al- 

 though it was not established as to all the ele- 

 ments, incited to further investigation. By 

 various corrections in estimating the atomic 

 weights of a few elements, and the discovery 

 of new substances which fitted into vacant 

 places in the series, the scope of this relation 

 has been extended so as to include fifty-one of 

 the elements, and chemists feel authorized to 

 regard it as a general law. 



