Mr. M. M. P. Muir on Chemical Notation. 3 



this be so, surely it becomas of vital importance to every 

 naturalist — and in the term naturalist we include the chemist 

 — to have a symbolical language which shall express the 

 weights of matter taking part in, or resulting from, any 

 action between what we call different kinds of matter. 



Now whatever theory we may hold concerning the consti- 

 tution of matter, it can scarcely be denied that our ordinary 

 formulas do tell us the weights of those kinds of matter which 

 take part in a given chemical reaction, or of those which 

 result from that reaction. To the principle of the conserva- 

 tion of matter the writer already quoted appears to object. 

 He would seemingly refuse his assent unless some one could 

 experimentally prove to him that a given chemical compound 

 has the same composition now that it had a hundred years 



Surely such a statement as this implies ignorance of the 

 meanings of a scientific generalization. Elsewhere Dr. Mills 

 speaks of the ideal reformer as one who " must have an infinite 

 capability of doubting." Is the infinity of this capability to 

 cause the ideal reformer to doubt every generalization which 

 rests upon well known and most thoroughly trustworthy facts, 

 because the special proof which he demands cannot, and that 

 from the very nature of the case, be forthcoming ? 



6. A chemical equation expresses the weights of the dif- 

 ferent kinds of matter taking part in the reaction formulated; 

 it therefore implies a dissimilarity of some sort between the 

 hinds of matter. The equation 2H 2 + 2 = 2H 2 implies that 

 the kind of matter represented by the symbol 2H 2 is different 

 in its essential properties from that represented by either of 

 the symbols 2 or 2H 2 0, — and, further, that the kind of 

 matter indicated by the last-mentioned symbol is in some way 

 composed of the two other kinds of matter. To such an 

 expression it has been objected that we do not know that the 

 substance represented by the symbol 2H 2 is composed of the 

 two substances 2H 2 and 2 , that we have reasons for be- 

 lieving that each of these three substances is equally homo- 

 geneous. Now it appears to me that we may use such a 

 chemical equation without committing ourselves to any theory 

 as to the manner in which the hydrogen and oxygen unite 

 together to form water. When we say in chemical short- 

 hand, 4 parts by weight of hydrogen, under certain con- 

 ditions, so react with 32 parts by weight of oxygen as to 

 produce 36 parts by weight of water, we state a fact. Plere 

 are three substances which exhibit to our senses different 

 phenomena ; with each of these substances certain definite 

 phenomena are invariably associated ; and we find that, under 



B 2 



