370 HISTORY OF SCIENCE. 



be discarded altogether. " Indeed, the establishment of a new nomen- 

 clature in any science ought to be considered as high treason against 

 our ancestors; as it is nothing less than an attempt to render their 

 writings unintelligible, to annihilate their discoveries, and to claim the 

 whole as our own property." So far Dr. T. Thomson. Now thus 

 Lavoisier expresses himself on the same topic : "The impossibility of 

 separating the nomenclature of a science from the science itself is 

 owing to this, that every branch of physical science must consist of 

 three things the series of facts which are the objects of the science, 

 the ideas which represent these facts, and the words by which these 

 ideas are expressed. Like three impressions of the same seal, the word 

 ought to produce the idea, and the idea ought to be a picture of the 

 fact. And as the ideas are preserved and communicated by means 

 of words, it necessarily follows that we cannot improve the language 

 of science without at the same time improving the science itself; neither 

 can we, on the other hand, improve a science without improving the 

 language or nomenclature which belongs to it. However certain the 

 facts of any science may be, and however just the ideas we may have 

 formed of these facts, we can communicate only false or imperfect 

 impressions of these ideas to others while we want words by which 

 they may be properly expressed." 



The system of names adopted by Lavoisier has the merit of a sim- 

 plicity which is perhaps unsuspected by persons unacquainted with 

 chemistry who casually meet with the names of chemical compounds. 

 It required no small exercise of the memory to recall the old names, 

 uncommon and barbarous as they are, and with no indications of the 

 class of substances to which they belong, and with little or no sugges- 

 tion of the relationships of the substances to each other. Such were 

 powder of algaroth, salt of alembroth, pompJwlix, turbith mineral, colco- 

 thar, etc., etc. And where the names indicated something of the con- 

 stituents or sources of the substances, they often at the same time 

 suggested false ideas as to its nature, thus : oil of vitriol ; butter of 

 antimony; sugar of lead; liver of sulphur ; flowers of zinc, etc., etc. 

 Without entering into unnecessary details, it will be easy by a few 

 examples to show the meaning of the French system of nomenclature. 

 The substances which result from the combination of a metal or other 

 body with oxygen were called oxides. Oxide was therefore the name 

 of a class of substances all agreeing in containing oxygen united with 

 another substance, and agreeing also by the characteristic of being 

 not acid, but capable of uniting with acids. The kind of substance 

 with which the oxygen is united is indicated by another word, thus 

 lead oxide or oxide of lead or plumbic (Lat. plumbum, lead) oxide, is the 

 name of a compound of lead with oxygen. And as not unfrequently 

 the same body unites with oxygen in several distinct proportions, the 

 particular oxide is indicated by a prefix to the generic, or by a suffix 

 to the specific name ; thus protoxide of iron or fenmr oxide means 



