SIB B. C. BEODIE ON THE CALCULUS OF CHEMICAL OPEEATIONS. 



837 



Boron .... 

 : Chloride of boron 



Boric methide . 

 Boric ethide . . 

 Trimethylic borate 

 Triethylic borate 

 Triamylic borate 



By similar reasoning to that employed in the case of silicon, we are led to assume 

 in this system of symbols 2=0, which results in the system given in the following 

 Table. 



Combinations of the Prime Factors u, I, d, x, . . . . and (3y 



Syifabol. 



a*'/3f'. 



If tve proceed to determine the most probable symbol of boron by aid of the hypo- 

 thesis A=V, or A=— , or A=— (Sec. VII. Group 2 (1)}, we have in case (i) A=V, 

 -^ =1, which admits of no integral solution, y^ being odd and y^ prime to ^2 J ^ case 



(ii) A= I' 2^=J, and ^2=1, yi=l; in case (iii) A=-, ^ =|, and 5^2=1, ^1=2. 



Hence the more probable symbols for boron (from these considerations) are a/Sf and a'j3J, 

 between which we cannot decide. 



The symbols which have been assigned to the gaseous compounds of the preceding 

 elements, silicon and boron, are to be regarded as the symbolic expression of the most 

 probable hypothesis as to their chemical constitution, which is consistent with the known 

 facts of gaseous combination. What weight, we may ask, is to be attached to such 

 conclusions 1 Now, it has akeady been reraai-ked that the weight to be given to such 

 hypotheses primarily depends upon the number of cases to which they are applicable. 

 But in the case of these elements we are acquainted only with a very limited number of 

 gaseous compounds ; and it must be admitted that, regarded exclusively from this point 



MDCCCLXVI. 5 X 



