STEVENS: FIXING AND HARDENING MATERIAL. 109g 
elass bead large enough to cover the mouth of the bucket, and 
then submerging the bucket in the fixative. But if an air pump 
can be had it is better to stopper the bucket with a cork which 1s 
trimmed flat on two sides so that the air may escape at the top as 
well as through the cloth bottom. Then the bucket should be 
placed in a bottle of water, or better,.5 per cent chromic acid, from 
which the air is then pumped, and after the atmospheric pressure 
is again turned on the material will immediately sink. The water 
or chromic acid should then be replaced at once with the intended 
fixative. If the material is in exceedingly small pieces, and would 
be likely to escape through the crevices left unstopped by the cork, 
it will be best to cork the bucket tightly and allow the air to escape 
only at the bottom. To wash out the fixative the buckets may be 
stoppered with corks sufficiently large to buoy them up, and then 
they may be floated in a tumbler of water into which water is kept 
slowly running; or the buckets may be suspended in the water by 
fastening their threads into notches ina stick placed across the 
tumbler. After the fixative is washed out the corks should be dis- 
carded and the buckets suspended in the different grades of alco- 
hol, etc., to about two-thirds of the depth of the bucket. Reagent 
bottles, conveniently arranged for suspending the buckets, may be 
prepared as shown in Fig. 3. The bottles 
are ordinary mustards, and the sticks for 
fastening the thread have been notched at- 
the ends for the thread and grooved at the 
center to receive the rubber band which 
fastens them to the neck of the bottle. We 
find it convenient to notch and groove the 
piece of wood from which the sticks are pre- 
pared before the sticks are cut off. The 
ia notches may be run with an ordinary mark- 
td hg ie ing guage, and the groove may be made and 
Oe the sticks cut off with a saw ina miter box. 
NY} 
at: 
A guage strip should be clamped to the 
Higas back of the miter box so that the sticks may 
be quickly cut to a uniform width. 
The material may remain in the buckets until brought into the 
paraffin on the oven, or even throughout the time it remains on the 
oven and until it is ready to be poured out for imbedding in the 
cold paraffin. 1 sometimes find it convenient to leave very small 
objects in the bucket on the oven until the solvent of the paraffin 
is evaporated, and then to lift the bucket quickly and plunge it 
