THE: MIcROScOoPE. 51 
bottle with an air-tight fitting cork, pierced by two short glass 
tubes; c,is a bottle partly filled with the injecting mixture. 
Through the cork of this bottle are two glass tubes, one of which 
is short, while the other reaches very nearly to the bottom of 
the bottle; d,is a brass nozzle with a stop-cock; 7, is a rubber 
tubing, which unites the different parts as seen in the figure. A 
y-shaped glass tube can be inserted midway in the rubber tube 
between the two bottles, so that two bottles of the injecting 
mixture can be attached to the one large bottle, b, which is 
empty at first. A third glass.tube can be placed in the cork of 
the bottle ce, which can be united by rubber tubing to a u-shaped 
glass tube partly filled with mercury, and thus the amount of 
pressure obtained. By raising the pail, the water descends the 
rubber tubing and compresses the air in the bottle, 6. The air 
is forced through the middle piece of rubber tubing and presses 
on the top of the injecting mixture in the bottle, ¢, which is 
forced up the glass tube, along the rubber tube to the canula, 
and into the animal or organ to be injected. If the force is not 
sufficient to fully inject the vessels, then the rubber tube can be 
detached from the pail of water and slipped over the end of a 
common Davidson’s syringe. With the aid of the bulb of the 
syringe, water can be forced into the first bottle, 4, sufficiently 
to give all the pressure desirable. 
GENERAL DIRECTIONS. 
1. Find the vessel you wish to inject and with the scissors 
cut a v-shaped opening in its walls, or with a knife make a lon- 
gitudinal slit. This is preferable to introducing the pipe directly 
in the end of a vessel, something almost impossible to do in the 
case of small vessels. The pipe should be filled with the inject- 
ing fluid before inserting it in the vessel. After filling, it is 
thrust in and tied round with silk, care being taken to bring the 
ends of the thread back around the hook on the pipe, so that 
there may be no danger of withdrawing it before the operation 
