Transactions of the Royal Society of Edinburgh. 351 



10. An Account of the Formation ofAlcoates. By Mr Thomas Graham. 

 — The bodies described in this paper are definite solid compounds of salts 

 and alcohol, analogous to the hydrates, and are imperfectly crystallizable. 

 Those which Mr Graham succeeded in forming are not numerous. They 

 were obtained simply by dissolving the salts, previously rendered anhy- 

 drous, in absolute alcohol, with the aid of heat. Upon cooling, the alco- 

 ates were deposited in the solid state. The crystallization was generally 

 compound, but in some cases singular crystalline forms appeared. The 

 crystals are transparent, decidedly soft, and easily fusible by heat in their 

 alcohol of crystallization, which is generally considerable, amounting in 

 one instance to nearly three-fourths of the weight of the crystals. 



The following are the alcoates obtained: — 



1. Alcoate of Chloride of Calcium. — This alcoate crystallizes in thin 

 transparent plates, which have the form of isosceles triangles, which form 

 compound crystals. They consist of 



2 atoms chloride of calcium, - 14 

 7 atoms alcohol, - - - 20.125 



34.125 

 2. Alcoate of Nitrate of Magnesia. — This alcoate is obtained in crystals 

 much smaller and less distinct than the former, but without any regular 

 form. It consists of 



1 atom nitrate of magnesia, - 9.25 



9 atoms alcohol, - 25.875 



35.125 



3. Alcoate of the Nitrate of Lime. — This salt is obtained sometimes in 

 irregular crystals. It consists of 



2 atoms nitrate of lime, - - 20.5 

 5 atoms of alcohol, - 14.375 



34.875 



4. Alcoate of Proto-chloride of Manganese. — This alcoate is obtained in 

 plates with ragged edges. It consists of 



1 atom protochloride of manganese, - 8 

 3 atoms alcohol, - 8.625 



16.625 

 5. Alcoate of Chloride of Zinc. — This alcoate, when concentrated so as 

 to be viscid, deposits small separate crystals of a regular shape. It con- 

 sists of 



2 atoms of chloride of zinc - 17.5 

 1 atom of alcohol - - - 2.875 



20.375 

 Mr Graham considers it probable that many more alcoates of salts may 

 be formed, particularly of the metallic chlorides ; but the great obstacle 



