270 Mr. W. H. Balmain on the Formation of Compounds of 



subject here. It has already been amply dealt with at the 

 commencement of my reply : I will only add, when it is con- 

 cluded from the hypothesis of a cubical arrangement of the 

 particles, acting by forces which vary according to the New- 

 tonian law, that the direction of one side of the cube is stable 

 and of one unstable (Earnshaw on the Nature of Molecular 

 Forces, Art. 15), ought we not to ask, Is it the hypothesis, or 

 the reasoning based on it which is erroneous ? Must it not of 

 necessity be the latter ? 



We have now done with the objections to the statical pos- 

 sibility of the law. It remains to reply to the two objections 

 to its dynamical applicability. It is fit that a matter so im- 

 portant as the rejection of a law which explains so many phe- 

 nomena (see Gauss, in the last No. of the Scientific Memoirs), 

 which has so strong an d priori probability, and which is the 

 proved law of material action, should rest on none but the 

 most unexceptionable evidence. Whatever may become of 

 the question ultimately, I trust that by rigidly examining that 

 evidence which has been afforded and showing its inadequacy, 

 I shall be considered as actuated by no captious or unphilo- 

 sophical spirit. My next communication will be a reply to 

 M. Cauchy, whose arguments being based on a refined ana- 

 lysis, can scarcely be answered without the use of similar 

 means. 



[To be continued.] 



XL VI. Observations on the Formation of Compounds of Boron 

 and Silicon with Nitrogen and certain Metals. By W. H. 

 Balmain, Esq., Lecturer on Chemistry in the Mechanics' 

 Institution, Liverpool*. 



/CONSIDERING the strong affinity existing between hy- 

 ^ drogen and nitrogen, and between carbon and nitrogen, 

 together with the circumstances under which they will com- 

 bine, and their chemical relations to boron and silicon, I was 

 led to imagine that the two latter elements must have a very 

 strong affinity for nitrogen, and concluded that they might 

 be caused to combine with it by double decomposition ; and, 

 bearing in mind the strong affinities of ammonia and cyano- 

 gen, it appeared probable that the compounds, if obtained, 

 would play an important part as chemical agents ; and I had 

 hopes that some of the bodies at present supposed to be ele- 

 mentary might prove to be compounds of nitrogen with these 

 or other elements. Some experiments instituted to establish 

 these points have been in a measure successful, but as they 

 form only a small part of the great number which will at once 

 * Communicated by Dr. Kane. 



