bichromate of potash in a quart of water. Cut the liver into
small parts, and place in the same solution as used for the kidneys;
change the solution after a day, and let them remain four or five weeks,
then change to spirits. The spleen and portions of the thin abdominal
muscles may be placed in a solution of three drachms chromic acid to one
quart of water, and transferred to alcohol after three or four weeks.
Carefully remove an eye and divide it behind the crystalline lens, put
the posterior portion in a solution made by dissolving fifteen grs.
chromic acid in five drachms water, and slowly adding five and one-half
ounces alcohol; change to spirits in two weeks. The lens should be put in
the same solution, but should remain a few days longer. Open the head,
remove the brain, and place transverse and longitudinal sections of it
in spirits for eighteen hours, then transfer to a solution of one drachm
chromic acid in a quart of water, and let it remain until hard enough to
cut. Place the uterus in a solution of one and one-half drachms chromic
acid in one quart of water, change to a new solution the next day, and at
the end of a month transfer to alcohol.
The bones from one of the legs should be carefully cleaned of its
muscles, cut into several pieces, and placed in a solution of fifteen and
one-half grains chromic acid, one-half drachm nitric acid, and six ounces
water. Change the fluid frequently until the bones are sufficiently
softened, and then change to alcohol.
_Section cutting_ machines for cutting sections can be procured of the
dealers, but a very simple and effective one can be easily made if one
does not wish to go to the expense of buying an instrument.
A strip of wood twelve or fourteen inches long and about two inches wide
has attached to its center a bridge-shaped piece of wood, a, Fig. 1. This
is covered with a brass plate, c, pierced with a hole one-half of an inch
in diameter. This hole extends through the wood, and is fitted with a
piston. Two long narrow inclined planes of nearly equal inclination, b,
b, grooved to slide on each other, are placed under the bridge; the lower
is to be fastened to the board; the end of the piston rests on the upper
one. The object from which we desire to cut a section is placed in the
hole, in the piston. If the upper plane be pushed in, the piston will be
forced upward, and with it the object. As the inclination of the plane is
very gradual, the vertical motion
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