94 PREPARATION OF CHLOROFORM. 
The chloroform is separated by decantation, agitated 
with water to wash it, and then with a weak solution of 
carbonate of soda to remove the chlorine ; it is then recti- 
fied over chloride of calcium in the water-bath. For medi- 
cal purposes I have considered it quite superfluous to admit 
it to a l^nrther rectification over sulphuric acid. The upper 
stratuui of the product from the distillation, and the waters 
used in washing are united, diluted with more water, and 
distilled in the water-bath. The chloroform soon passes 
over, carrying with it a little water and spirit. It is purified 
as above described. 
The principal difficulty in the preparation of chloroform 
is the necessity of working with very dilute chloride of 
lime, from fear of other bodies originating, especially of 
acetic products, which it would be almost impossible to 
separate. Hence the necessity of operating in vessels of 
large dimensions, although working with very small quan- 
tities of alcohol. It must moreover be remembered that 
chloroform appears to be only a secondary product. In 
the violent reaction which ensues between the hypochlorite 
of lime and alcohol, there is always much less obtained 
than theory would lead us to expect. Fortunately eacli 
operation occupies but little time, and several distillations 
may be made one after the other in the course of a day. 
My first eff'orts were restricted to determine the most 
advantageous proportions of chloride of lime, water and 
alcohol. I have likewise made some experiments to ascer- 
tain the influence of a longer or shorter contact, and I am 
induced to think that the operation is the more productive 
he quicker it is efl'ected. I believe that it is very advan- 
tageous to mix the pulverized chloride of lime in hot water, 
in order that it may more rapidly attain the temperature of 
176°, requisite for the production of chloroform. 
A great deal of the chloroform sold at first was not suffi- 
ciently pure. I may observe, that notwithstanding its appa- 
rent fluidity it is very heavy, and this furnishes a ready 
