IOWA ACADEMY OF SCIENCES. 
55 
1. Effect of various stimuli upon motor nerve or curarized 
muscle, as thermal, mechanical, electrical and chemical. 
2. Effect of electrical stimuli of varying intensities. 
3. Effect of repeated stimuli — followed by tetanus. 
4. Result of continued fatigue. 
5. The “Maker” shock compared with the “Break.” 
6 . Conditions affecting degree of muscular contraction, as 
amount of resistance, temperature, poisons, etc. 
Numerous other uses will occur to the student in advanced 
physiology, in which the recording apparatus will be of ser- 
vice. 
To some it may be interesting to note that the tracings upon 
smoked paper may be preserved indefinitely, by carefully 
removing it from the cylinder, and passing it through an 
alcholic solution of white shellac, then allowing it to dry. If 
the tracing thus preserved be oiled, it becomes thin enough to 
be used for printing blue print copies of it. 
VOLATILITY OF MERCURIC CHLORIDE. 
BY ABBOTT C. PAGE. 
[Abstract.] 
Solutions of mercuric chloride were evaporated on a water 
bath with the following results: 
SOLUTION. 
ALTER ADDITION OF 
EVAPORATED TO 
LOSS OF HgOlg- 
A 50 CC 
A 50 CC 
dryness 
35 cc 
.0133 grm 
.0036 grm 
50 CC water 
A 50 CC 
20 cc dil HOI 
25 cc 
.0063 grm 
A 5') CC 
1 grm KOI 
dryness 
.0008 grm 
A 50 cc 
1 grm plus 50 cc water 
25 cc 
.0002 grm 
B 13.5 cc 
3 .0354 grm KOI ) 
i plus 2 cc HOI [ 
5 cc 
.0001 grm 
Solution A contained .2322 gram mercuric chloride in 50 cc, 
and solution B .1295 gram in 12.5 cc. The author considers 
that these results indicate the probable existence of the com- 
pound K Hg CI 3 . n, O. 
