128 DONALDSON. [Vouslixe 
LABLE 2: 
Showing the percentage loss in weight by drainage. Specimens from 27, 
bichromate of potash :— 
spo eedinitsnaha Spsc. 2. | Spec. 2. | Spec. 3. | Spec. 3. | Spec. 4. | Spec. 5. | AVERAGE. 
2 0.9 0.8 0.36 0.9 0.60 0.5 “0.66 
4 1-3 Ta3 0.53 1.4 0.79 0.8 1.02 
6 Te ui 0.77 1.6 Te2 0.9 1.24 
8 1.6 Ey 0.8 1-7 1) 1.0 Teas 
Specimens from 94.5% alcohol : — 
AFTER DRAINING. 
MERGES. SPEC. 2. SPEC. 4. SPEC. 1. SPEC, 3. AVERAGE. 
2 0.9 0.6 0.8 0.8 0.77 
4 1.3 1.0 1.0 I.I I.I 
6 1.6 1.4 1.4 1.6 1.5 
8 1.9 1.4 1.6 1.8 1.6 
These figures also show how similar the two weighings of 
the same specimen can be. The error due to weighing is 
therefore slight. 
Extent of Drainage. —In this connection it must be remem- 
bered that drainage cannot be carried on very far without 
permanently altering the weight of the specimen. 
The following figures show the loss in specimens already 
drained for seven minutes, and then left somewhat exposed : 
A hemiencephalon hardened for 34 days ina 2}% solution 
of bichromate of potash was drained seven minutes, after which 
it weighed 82.3 grms. It was then wrapped in a thin layer of 
cotton saturated with the same solution, and the whole covered 
with paraffin paper. After 24 hours under these conditions it 
weighed 80.7 grms., thus having lost 2%. On being left for 
the next five days in the original fluid, it weighed 81.6 grms., 
thus showing a permanent loss of 0.9%. 
This loss was not made good later. A second specimen 
hardened in a 2}% solution of bichromate of potash, plus 
6 
its volume of 95% alcohol showed, after similar treatment, 
