AtOMIC PmNCIPLES OF CHEMISTRY. 14? 



time, that I have proceeded far enough in the develope- « Vj 



luent of the truth of a proposition almost self evident ; if 

 not t may resume it on some future occasion. 



The 2d, 3d, and 4th rules are necessarily consequent to 2^, 3d, and 

 the 1st. When an element A has an affinity for another ' ^" *** 

 B, 1 see no mechanical reason why it should not take as 

 many atoms of B as are presented to it, and can possibly 

 come into contact with it (which may probably be 12 in 

 general), except so far as the repulsion of the atoms of Q 

 among themselves are more than a match for the attraction of 

 an atom of A. Now this repulsion begins with 2 atoms of 

 B to one of A, in which case the 2 atoms of B are dia- 

 metrically opposed; it increases with 3 atoms of B to 1 of 

 A, in which case the atoms of B are only 120° asunder; 

 with 4 atoms of B it is still greater as the distance is then 

 only 90"; and soon in proportion to the number of atoms*. 

 It is evident then from these positions, that, as far as powers 

 of attraction and repulsion are concerned, (and we know «f 

 no other in chemistry) binary compounds must first be 

 formed in the ordinary course of things, then ternary, and 

 so on, till the repulsion of the atoms of B (or A, whichever 

 happens to be on the surface of the other), refuse to admit 

 any more. 



1 shall now proceed to the 5th, 6th and 7th, or remain- 6th, 6tb, and 

 ing rules, which Dr. Bostock has not quoted, but of which '^^^'■"'•^• 

 he is equally in want of an explanation, or he would not 

 have formed such conjectures as that" it seems the most na- 

 tural to regard the sulphuric acid as the binary compound 

 of sulphur and oxigen," and that carbonic acid is a binary 

 and carbonic oxide a ternary compound, and that nitric 

 acid is a binary compound of azote and oxigen and nitrous 

 gas a ternary, and that nitrous oxide is biliary, &c. (pao-e 



• I find from the principles of statics, that, upon the supposition of 

 spherical atoms of eqnnl size, and that the law of repulsion after chemi- 

 cal union is the same r\s before, namely, reciprocally as the central dis- 

 tance, the repulsion of any one aiom ol B upon another of B, to separate 

 it from A, is a constant quantity, on whatever point of the surface of A 

 it may be placed ; so that when there are 3 atoms of B, the 3d atouji is 

 repelled twice as much b) the other two as it would be by a single atom -^ 



placed diametrically opposite. When there are 4 atoms, thea the 4th ii * 

 three limes as much repelled, Ac. 



L « 887, 



