69 
ture was not due so much to the cold causing a reduction in the quan- 
tity of formaldehyde given off as to polymerization of the liberated 
formaldehyde resulting from the cold. 
II. EXPERIMENT WITH DILUTED FORMALIN AND PERMANGANATE. 
Two experiments were made with 0.6 c. c. formalin diluted with 
0.3 c. c. water and 0.375 gm. of powdered permanganate; these are 
the same proportions as used in most of the experiments in Table 2. 
The procedure was the same as described above. 
Experiment. 
Formalde- 
hyde 
found in 
bottle. 
Formalde- 
hyde 
found in 
residue. 
Total 
found. 
I 
Per cent. 
31.00 
32. 16 
Per cent. 
34.23 
34.04 
Per cent. 
65.23 
66.20 
II 
The percentage yield was about the same as that given in Table 2, 
but less than that in the previous experiments (Table 6) with undi- 
luted formalin. The formaldehyde remaining with the residue w T as 
about the same as in the previous experiments where powdered per- 
manganate was used. The total formaldehyde found was less than in 
the experiments with undiluted formalin, thus indicating a greater 
destruction of formaldehyde. 
III. EXPERIMENTS ON DRYING FORMALDEHYDE GAS BY ANHYDROUS CAL- 
CIUM CHLORIDE. 
The bottle was charged as in the previous cases, using 0.7 c. c. of 
formalin and 0.35 gm. of powdered permanganate. The crucible was 
removed between 15 and 20 minuted after it had been introduced iilto 
the bottle. 
The drying apparatus consisted of a curved tray, made of a piece of 
sheet zinc about 1.75 inches wide, 10 inches long, and 1.25 inches deep. 
One end of the tray was closed by bringing the edges together; the 
other end was curved around a wooden handle, which fitted into a hole 
in a cork. The latter fitted the mouth of the bottle. 
After removing the crucible the bottle was laid on its side. Granu- 
lated calcium chloride was placed in the tray in a layer about an inch 
deep ; then as quickly as possible the stopper of the bottle was removed 
and the tray introduced and held in place by means of the stopper 
attached to its handle, which fitted the neck of the bottle. 
After 1 hour, which seemed ample time to thoroughly dry the atmos- 
phere in the bottle because of the large surface of calcium chloride 
exposed, the stopper and tray were removed and replaced by the first 
one. 
