Prof. Williamson on Chemical Nomenclature. 465 



In the course of the discussion which took place on the sub- 

 ject, I had occasion to point out that, inasmuch as salts in which 

 the base is hydrogen, such as hydric nitrate, hydric sulphate, 

 hydric phosphate, &c, are admitted to be analogous in their 

 constitution and properties to the salts of the regular metals, 

 such as silver, potassium, &c, it is desirable, when describing 

 their reactions, to designate them by names bearing a corre- 

 sponding analogy to the names of the salts of silver, potassium, &c; 

 that in describing the reactions of double salts containing as 

 base partly hydrogen, partly some heavier metal, such as com- 

 mon rhombic phosphate, H Na 2 PO 4 , it is not only desirable to 

 introduce the name of the hydrogen in a form similar to that of 

 the other metal, but it is really not possible to obtain systematic 

 and consistent names without representing in them the metallic 

 functions of the hydrogen; that when hydrogen is in the place of 

 an acid or chlorous constituent of a salt, it must be described by 

 a term which represents the fact of its having such functions. 



In fact it is not allowable to apply to hydrogen-salts names 

 which conceal their analogy with other salts, or which imply the 

 absence of saline constitution in hydrogen- salts. Thus it is a 

 faulty expression to say that the common process for preparing 

 so-called nitric acid consists in the action of sulphuric acid on 

 potassic nitrate, forming potassic bisulphate and nitric acid ; for 

 such an expression conveys the idea of a mere displacement of 

 one acid by another, whereas the process is admitted to be an 

 interchange of half the hydrogen in hydric sulphate with potas- 

 sium in potassic nitrate, forming hydropotassic sulphate and 

 hydric nitrate. 



It was admitted by all who spoke on the subject at the Che- 

 mical Society, that hydrogen-salts must in exact language be 

 named similarly to other salts ; and one distinguished member 

 mentioned that, in describing to students such a reaction as the 

 above, he uses such terms as sulphate of hydrogen and nitrate 

 of hydrogen. 



It was at first supposed by some members that I advocated 

 the immediate introduction of systematic and accurate names 

 into common and popular language. The learned member felt 

 alarm at the danger of having to speak of mercurous chloride 

 instead of "calomel," manganic peroxide instead of "manga- 

 nese," hydric sulphate instead of "sulphuric acid," &c; and 

 manufacturers would certainly not have received with favour a 

 proposal to give up the term "soda" for sodic carbonate, to 

 say arsenious acid instead of " arsenic." 



I accordingly hastened to explain that my suggestions towards 

 improving our systematic nomenclature were only expected, if 

 adopted, to react gradually upon the popular language, and that 



