92 @C. Marignac—Chemical Equivalents and Atomic Weights. 
analogy, and particularly if they do not perform the same 
functions, the idea of equivalence has no meaning. I defy 
anybody to give a general definition of equivalents which 
justifies the weight 14, adopted for nitrogen. In volume, it 
eure to the equivalents of hydrogen and of chlorine, 
t it has not the same chemical value. It has the same 
wictanah value as the equivalents of phosphorus and arsenic, 
t 
equivalents of oxygen, of reac gael and of most metals) Why 
then should this number exist ? 
If, instead of starting Pain a general definition, which does 
not exist, we try to find the meaning of equivalents in the 
methods employed i in determining them, we are led to the 
following conclusion 
It is proved by experience that we may assign to a body, 
it simple or compound, various weights, ‘multiples of the same 
number, and that these weights express the proportions accord- 
ing to which all bodies combine with one another. We ma 
choose one of these weights to express the equivalent of the 
body. All combinations may then be represented as the 
and, if the equivalent is — ented by a symbol (in general 
the first letter of the name of oe element), combinations may 
represented by foeeh olen which are not generally compli- 
eated. This is, after all, the only condition required of equiv- 
— and hence the only general definition, although not 
very precise, which can be given is that the equivalent repre- 
—— for a element or Sceeey: Sing nd body one of the weights 
en bodies are an nai and have the same chemical 
denice their equivalents are represented by the weights 
which replace each other in analogous combinations. Let us 
note, however, that this rule is not followed for compound 
bodies, such as bases and acids, whose so-called equivalents 
are weights which often have: very sean values of com- 
‘undamental principle of equivalents has been entirely aban- 
doned for compound bodies, and, in its stead, a method has 
been adopted, which has been borrowed from the atomic 
