SIE B, C. BEODIE ON THE CALCULUS OF CHEMICAL OPERATIONS. 



835 



, Symbol. 



Chloride of silicon a*xV'. 



Silicon-ethyl a'Vff*'. 



Silicate of ethyl a' V$V'. 



Silicate of amyl a"*'"^ o'*. 



Monochlorhydrine of silicate of ethyl . . a*%**|V>. 



Now there is but one hypothesis which can be made as to the value of Zj, which is at 

 once necessary and sufficient, namely that Zy=\. The reasoning here employed is of 

 the same kind as that by which the symbols of the combinations of carbon were deter- 

 mined ; but the observations being few, the conclusion is of a less certain character. 

 By a similar argument also to that before used in regard to the value of A, it may 

 be shown that there is great reason to believe that z=l, or =2, or =4. It is not 

 necessary, however, to make any other assumption than that z=l, in which case the 

 density of silicon- vapour is a multiple of 14, which is all that can be asserted with pro- 

 bability. 



Putting Zi=l, we have the following symbols: — 



Combinations of the Prime Factors a, ^, ^, ^j, . . , . and a. 



Name of substance. 



Silicon 



Silica 



Monohydrated silicic acid 



Stilphide of silicon 



Chloride of silicon 



Bromide of silicon 



Silicon-ethyl 



Silicate of ethyl 



Silicate of amyl 



Monochlorhydrin of silicate of ethyl 



Prime factor. 



Symbol. 



a'/3V 





Absolute weight, 

 in grammes. 



1-251 



sx 1-251 

 2-682 

 3-486 

 4-112 

 7-598 

 15-554 

 6-436 

 9-297 

 11-442 

 8-872 



Belativo weight. 



14 



2X14 



30 



39 



46 



85 

 174 



72 

 104 

 128 



99-25 



(3) Symbol of Boron. — In the decomposition of the chloride of boron into its elements, 

 one volume of that substance is decomposed with the formation of 1^ volume of chlorine. 

 Hence, if y^ be the smallest integral number of imits of the chloride of boron decom- 

 posed, and ^2 t^6 number of units of boron formed in the decomposition, ^=o ; and 



putting a^xi^'/S? as the symbol of the terchloride of boron, and oT^^ as the symbol of 

 boron. 



whence 



(a":t'"'/3r')'^> = (a;^)'*.(«V/3r')", 



