106 ANNUAL OF SCIENTIFIC DISCOVERY. 



and alumina, prepared and used in such a manner as to be free 

 from the presence of ammonia, potash, soda, lime, or nitric acid, 

 or from any acid or alkaline reaction. 2. The electro-deposition 

 of nickel by means of a solution of the double sulphate of nickel 

 and potash, prepared and used in such a manner as to be free 

 from the presence of ammonia, soda, alumina, lime, or nitric 

 acid, or from any acid or alkaline reaction. 3. The electro- 

 deposition of nickel by means of a solution of the double sul- 

 phate of nickel and magnesia, prepared and used in such a man- 

 ner as to be free from the presence of potash, soda, alumina, lime, 

 or nitric acid, or from any acid or alkaline reaction. 



USE OF BORAX IN GLASS MANUFACTURE. 



| 



MM. Maes & Clemendot, glass manufacturers at Clichy, pro- 

 duce a crystal as fine as the best Baccarat and St. Louis crystal 

 by using boracic acid. 



The presence of this flux allows a modification in the composi- 

 tion of the crystal, as the oxide of zinc can then be substituted 

 for the oxide of lead ; and soda, lime, or barytes can thus replace 

 potassa. 



The barosilicates of zinc and potassa, of potassa and barytes, 

 of soda and zinc, manufactured by Maes & Clemendot, are re- 

 markable for their limpidity and whiteness. The following are 

 the proportions : 



Silicious sand (white), 261 225 



Minium, 2G1 225 



Potassa^lst quality), 60 52 



Borax, 18 4 



Nitro, 18 3 



Manganese, 18 1 



Arsonious acid, 18 1 



Refuse of former operations, 18 89 



GLYCERINE CEMENT.' 



Professor Hirzel, of Leipzig, has discovered an important use 

 of glycerine that ouo'ht to be more generally known. He finds 



^J \J Vj - 



that when glycerine is mixed with fine and well-dried litharge, 

 it yields a cement that is capable of a large number of applica- 

 tions. 



All metals and nearly all solid bodies can be bound together by 

 this cement ; it is said to harden underwater as readily as in the air, 

 and to resist a temperature of 500. It is especially recom- 

 mended for such pieces of apparatus as are exposed to the action 

 of chlorine, -- hydrochloric acid, sulphuric acid, sulphurous acid, 

 and nitric acid ; also the vapor of alcohol, ether, and bisulphide 

 of carbon, as none of these agents act upon it. The cement can 

 be used in steam engines, pumps, foundations for machinery, 

 and, finally, as a substitute for plaster in galvano-plastic and 



