186 On some Reactions of the Salts of Lime and Magnesia. 
hydrochloric acid, which dissolved ‘178 of carbonates con- 
taining only 12°8 p. c. of carbonate of lime, leaving ‘116 grm. of 
insoluble silicious residue. 
40. In a repetition of the above experiments the carbonates 
were treated with acetic acid at 32° F. till effervescence ceased, and 
of the remaining double carbonate was digested for 
the alkaline carbonate in another. In another experiment, a 
mixture of ter-hydrated carbonate of magnesia and carbonate of 
lime with water and carbonate of soda, was employed. All o 
these were heated in metallic tubes to from 130° to 200° C. and 
the products digested for a long time with acetic acid at 60° F. 
ese experiments were made at a time when I had not deter- 
of 
omg in the boiler of a steam engine to a temperature of from 
20° to 180° C. for several hours every day danny ten weeks. 
The washed residue was then digested with acetic acid only until 
effervescence ceased ; after which it was completely soluble in hy- 
drochlorie es and gave carbonate of lime 46:3, carbonate 
ite Be 
nesia, whether (1) as magnesia alba in presence of excess of cat- 
bonic acid, from bicarbonate of soda, or (2) a ter-hydrated carbon- 
of magnesia, or (4) by carbonate of lime from a solution of chlo- 
rid of page at an elevated temperature, or (5) as separa 
from the double carbonate of magnesia and soda by a solution of 
chlorid of calcium, will in the presence of water unite directly 
with carbonate of lime to form a double carbonate of lime and 
