348 J. M. Ordway on Waterglass. 
manence, and it is probable that the best effect would be attained 
by using a silicate alone, many times and at distant intervals. 
Kuhlmann meets the difficulty by a plan theoretically perfect, 
but involving too much expense, which is to use silicate of pot- 
ash and render both constituents insoluble with fluosilicie acid. 
To impart a more agreeable color than some stones naturally 
possess, Kuhlmann impregnates them, first of all, with a salt of 
iron, manganese, copper, or chrome. The silicate afterwar 
With regard to stone, silicatization is of little importance 
ieti artificial 
Fuchs in his first memoir, showed the possibility of making 
an artificial stone with clay, sand, and a solution of silicate © 
soda. Such a mixture after being moulded into any desired form 
without exposing the mixture, after moulding and drying, to a 
heat strong enough to revitrify the silicate. By such treatmen 
baked ware should, of course, be slowly cooled so that th 
menting material may become properly annealed. “s 
In 1844, Ransome took out a patent in England for a sto 1 
ae arte with liquor silicum, limestone powder, or chalk, ee 
sand. His process is a rather expensive one, but the art 
os is said to be of excellent quality. There 15 eens. 2 
lieve that liquor silicum, is less suitable for such purpose ” 
the far cheaper sesquisilicate or bisilieate of soda. In na 
trials in a small way I have been unable to get a good ware bt 
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