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wise wonderfully laborious and refined experimental work; and that 
a number which is an integer multiple of the combining weight 
of hydrogen is obtained by Dumas as the combining weight of 
one of those elements to which Stas assigned a fractional number. 
Analogies may be traced between the properties, more especially 
between certain physical constants, of groups of elements, and 
the properties of substances which are certainly compounds, in 
varying proportions, of two distinct elements. Further it is known 
that one and the same element may exist under what are tech- 
nically termed allotropic modifications ; that is to say, that a 
substance which we are unable to decompose into any simpler 
form of matter may nevertheless exhibit, under varying con- 
ditions, different physical, and to a certain extent also different 
chemical, properties. 
Such analogies, details of which I cannot here recapitu- 
late, give a certain degree of plausibility to the theory that 
the so-called elements are really non-elementary bodies. But 
such analogies, it may be urged, are shadowy and vague 
at the best. Twist it how you may, the fact remains that 
we can decompose those bodies which we call compounds, and 
that we cannot decompose those bodies which we call elements. 
No one — triumphantly remarks the orthodox chemist — no one has 
yet succeeded in decomposing an element. Are you sure of this ? 
Were one to decompose sodium to-morrow, it is by no means 
certain that one could recognise the products of the decomposi- 
tion. The ordinary conditions of temperature and pressure would 
be entirely altered when one succeeded in decomposing sodium; 
and under these altered conditions no small difficulty would be 
encountered in endeavouring to determine the fact of decom- 
position. We may have decomposed the elements, and not 
have discovered our own success. New problems require new 
methods for their solution. Anyone who should attempt the 
study of what I may call the Elementary Elements with the 
ordinary appliances of the laboratory, would certainly be 
doomed to failure. 
Mr. Lockyer has attempted to solve the problem presented 
by the elements by combining a new series of experiments with 
a new method of observation. He has observed the phenomena 
which occur when certain elements are exposed to the action of 
intense heat by the aid of perhaps the only instrument at present 
known, which is capable of giving a satisfactory account of such 
phenomena — the spectroscope. 
The paper in which Mr. Lockyer propounds his views of the 
nature of the elements is entitled, “ Discussion of the working 
Hypothesis that the so-called Elements are Compound Bodies.” At 
the very outset, therefore, the author is careful to abstain from 
saying that he has succeeded in decomposing the elements. 
