96" 
ON CHLOROFORM. 
lice, it is indispensably necessary to ascertain whether it be 
pure. M. Mialhe finds that the following is a very delicate 
test of thejpresence of alcohol in chlorofornfi : — Place some 
distilled water in a tube or glass, and drop on it a snaall 
quantity of chloroform. The greater part sinks immediately 
to the bottom of the vessel, owing to its great density (sp. 
gr. 1.4S.) A small quantity floats by repulsion, but may 
be made to fall in small globules by agitation. If the chlo- 
roform be pure, it remains transparent at the bottom of the 
vessel ; but if it contain only a small portion of alcohol, the 
globules acquire a milky opacity." 
Assuming the whole of the facts to be as stated by M. 
Mialhe, this test would appear to be a very delicate one, 
for we have found that som.e specimens of chloroform, which 
remained transparent when added to water, acquired a 
perceptible opalescence if treated in the same way after the 
addition of one-thousandth part of absolute alcohol, and 
the effect became marked when the alcohol amounted to 
one three-hundredth. If rectified spirit be added in small 
quantity to transparent chloroform, the mixture becomes at 
once opalescent, although a larger quantity of spirit forms 
a clear solution ; so that when transparent chloroform con- 
tains minute quantities of alcohol, it seems probable that 
the latter is in the anhydrous or nearly anhydrous condi- 
tion, as stated by Mialhe, and that the milkiness which 
takes place, on the addition of water, is the consequence of 
the hydration of the alcohol. This milkiness generally 
disappears^ with a slight increase of temperature, the mo- 
mentary application of a warm hand to the tube containing 
the mixture being sufficient to render it transparent. It 
may be inferred from this, that the test which appears to 
be so delicate at a low temperature would uot be equally, 
if at all, delicate in warm weather. 
When chloroform has become milky from contact with 
water, it immediately reacquires its transparency on shaking 
it with a little fused chloride of calcium. Fhis effec is not 
