of a metallic Substance called Palladium . 319 
speculative, to consider the metallic bodies in an order which 
may bring together those which possess the greatest number of 
similar characters. 
As an instance of this approximation, it may be observed, that 
nickel and cobalt strongly participate in the properties of cop- 
per and iron. The two former metals were long regarded as 
mixtures ; and the doubts of the ancient chemists, who feared 
to pronounce as to their nature, may still be proved to have 
more foundation in truth than the assertion of the moderns, 
who have declared them to be simple. Acted upon by the same 
menstrua, forming insoluble compounds with the same acids, 
and soluble alike in other substances, they have but one or two 
marked properties that lead us to consider them as distinct 
metals. But palladium has at least five or six characters, as 
strong as those of any metal whatsoever, that distinguish it, not 
only from its elements, but also from all other metals. 
Among the earths, this approximation is still more apparent. 
A leading character of these substances is, their tendency to 
enter into saline combinations, in which they receive new pro- 
perties, and perform new functions. If we rank them according 
to this general tendency, we shall have the following order : 
barytes and strontia ; lime and magnesia ; glucine and alumina ; 
zircon and silica. And, if we consider them two by two in 
this order, which is a natural one, we shall bring together 
precisely those which differ by the smallest number of chemical 
characters. 
This investigation might be pursued still further; but we 
must wait the result of experiments : a wide field is open for 
research. In the dark ages of chemistry, the object was, to rival 
nature ; and the substance which the adepts of those days were 
Ttg 
