MIXED HYDRATE-AMIDES. 19 



or by amidogen ; or we may replace one of them by eurhyzen 

 and the other by amidogen ; whilst in bodies containing three or 

 four atoms of chlorine, the possible number of derived bodies 

 increases in a very rapid manner, according to the ordinary 

 algebraic rule of combinations. I have here written down the 

 names of a few well-known double chloro-hydrates, chloro- 

 amides, and hydrate -amides, by way of illustration. 



Mixed Hydrate-Amides, &c. 



CuF a Cupric difluoride 



CuF.HO Cupric fluorhydrate 



HgCl a Mercuric dichloride 



HgCl.H,N Mercuric chloramide 



C 3 N 3 .C1 3 Cyanuric trichloride 



C 3 N 3 .Cl(H a N), Cyanuric chloro-diamide 



C 3 N 3 (HO) 3 Cyanurie trihydrate 



C 3 N 3 (HO) a (H 2 N) Cyanuric dihydrate-amide 



C 3 N 3 (HO) (H,N) a Cyanuric hydrate-diamide 



C 3 N 3 (H,N) 3 Cyanuric triamide 



First of all we have difluoride of copper, or cupric difluoride, 

 followed by cupric fluorhydrate. Next we have mercuric di- 

 chloride or corrosive sublimate, and then mercuric chloramide, 

 or white precipitate, a body in which one of the original chlorine 

 atoms is replaced by amidogen. Next we come to cyanuric tri- 

 chloride and its numerous derivatives, in the first of which, 

 namely, cyanuric chloro-diamide, two of the original chlorine 

 atoms are replaced by amidogen. Then we have in succession 

 cyanuric trihydrate or ordinary pyro-uric acid, cyanuric dihy- 

 drate-amide or melanuric acid, cyanuric hydrate-diamide or 

 ammeline, and lastly cyanuric triamide or melamine, a body 

 produced, as I have already said, by the action of heat upon 

 urea. 



(18.) Let me give you one more illustration of this relation- 

 ship. I have said that urea CH 4 N 2 0, is an ammoniated form of 

 carbonic acid ; but we are acquainted with another urinary 

 product, namely, guanidine CH 5 N 3 , which is an ammoniated 



c2 



