THE CONSTITUTION OF MATTER. 
039 
separated ; for chemistry has to do solely with body, and in treating of body we 
include matter. 
But I freely congratulate Provincial Atom upon his very successful exposition 
of the applications to which the use of the terms matter, substance, body , ought 
to be restricted. I only fear difficulties in the setting up of these boundaries 
upon the territory of physical inquiry. 
Following the sections of his second paper, I have but a few remarks to offer. 
§ 1 . The definition of cause which I had in my mind was one which I became 
acquainted with as a student, and which will be found in several works on logic. 
The cause of any given effect is usually taken to be that circumstance which 
forms the crowning point of the assemblage of conditions essential to the pro¬ 
duction of that effect. It is the last hair which turns the scale. 
In the production of a chemical reaction, e. g. the formation of a precipitate, 
there must be a certain material to operate upon, which must be under certain 
conditions of solution, temperature, and the like, before the addition of the re¬ 
agent will bring about the desired object. Aud I merely intended to allude to 
the obvious circumstance that if we can imagine the reversal of any one natural 
law,* the whole order of the universe would be changed. 
§ 2. Provincial Atom appears to have misunderstood not only my statements' 
with regard to the composition of graphitic acid, but also one of the most obvious 
requirements of the atomic theory in its chemical aspect. A really valid objec¬ 
tion to any allusion to that substance w r ould have been this: that our knowledge 
of it is at present so incomplete, that without further investigation, no conclu¬ 
sive argument can be based upon it. Carbon, in its ordinary combinations, ex¬ 
hibits a combining weight 12 times that of hydrogen ; in the peculiar condition 
in which it gives rise to graphitic acid, it combines in a proportion which is 33 
times that of hydrogen. If this latter number had been 24 or 36, it would have 
been easy to understand how two “'atoms’" of the ordinary kind in the one case, 
or three in the other, could, coalesce to form a new unit of combination ; but 
no relation of this kind exists between such numbers as 12. and 33. Now the 
atoms thrust upon us by the atomic theory are, by the hypothesis, indivisible. 
If divisible, the whole theory collapses; if indivisible, fractional parts of them 
cannot be admitted into our formulae and reasonings. The manifest inconveni¬ 
ence of frequently employing such formulae, even to express proportions, would 
alone decide against them. 
§ 3. It would occupy too much space to discuss fully Faraday’s-arguments. 
I can therefore only observe that L derive no assistance in endeavouring to ima¬ 
gine the rationale of electrical conduction and insulation from the suggestion of 
Provincial Atom, as to the possibility of an atmosphere investing each atom in 
a body. For it immediately occurs to one to inquire what is the atmosphere so 
assumed ? Either it is of a material nature or not: if not, if it is really empty 
space, then Faraday’s argument has only one alternative, viz. that which we call 
electrical conduction must be an effect springing from some hidden cause, and 
related to it somewhat in the way that weight is to gravitation. The influence 
then which gives rise to electrical conduction must be capable of operating 
through perfectly vacuous space, just as we believe gravitation is capable of 
acting 5 if, on the contrary, the assumed atmosphere is any way analogous in 
constitution to the central atoms themselves, the same difficulties have to be got 
over which are encountered in treating of the constitution of body. 
Provincial Atom inquires what becomes of the nine volumes when ten volumes 
of air are condensed into one ; does he purposely overlook the fact that at any 
rate some portion of the x is represented by no other than the heat which is 
given out during the experiment? 
* As, for instance, the contraction instead of expansion of bodies by increasing their tern 
per at iu - e. 
