254 
SELECTED ARTICLES. 
on a weighed filter and its weight determined. This analysis 
gave the following results: — 
Experiment. Precipitate. Chlorine in liquid. 
1 91.3 12.6 
2 92.4 13.3 
3 92.9 13.15 
4 95.4 12.7 
5 93.4 12.95 
Mean, 93.1 13.00 
One hundred grains of the sublimate contain 74.09 of mer- 
cury and 25.91 of chlorine. Thus the quantity of chlorine 
remaining in solution was one-half less than that existing in 
the sublimate; therefore, in 93.1 of the white precipitate, we 
have 74.09 of mercury, and 12.91 of chlorine. 
2. The white precipitate, subjected to heat, gives off gaseous 
matter, water and calomel. The experiment is thus con- 
ducted: a bulb is blown on the end of a tube, which is then 
w^eighed, the precipitate is next introduced into it, and its 
quantity determined by weighing the whole. The heat is 
applied so as to sublime the calomel without loss, taking care 
to drive off any water which may have condensed on the 
sides of the tube; this calomel is black, but on allowing the 
apparatus to cool in the air and then re-heating the calomel it 
becomes perfectly white. The tube is again weighed, the 
loss of weight gives the quantity of water and gaseous mat- 
ter; the excess over the weight of the empty tube gives the 
quantity of calomel, and by this we have the quantity of mer- 
cury and chlorine. 
No. of exper. Matter used. Calomel. Calomel per cent. 
1 20.42 18.95 92.80 
2 19.42 18.07 92.53 
3 12.14 11.28 92.91 
4 14.71 13.79 93.68 
