NEW FORM OF ETHER MICROTOME. 231 
air-hole, and the tubes, laid one over the other, are soldered together 
in this position; the free ends of the tubes are then connected 
with the air bellows and the ether bottle respectively by means of 
india-rubber tubing, and this part of the apparatus is complete. 
The microtome (see fig. 58) consists of the framework, and the 
mechanism for raising the section. The framework is of '%-inch 
mahogany, and is in the form of a base with two upright parallel 
pieces screwed on to it. The base (A), which is about 2% by 4 
inches, is bored to allow the tubes for raising the secticn to pass up 
between the parallel pieces, and has a projecting part at one side 
to allow of its being clamped to the table (M’). The two parallel 
parts (BB), which are of the same 14-inch mahogany, stand about 
1 apart; they are 4 inches long, and, rising to 1 inch high, each 
carries on the upper surface a piece of 14-inch plate glass (CC) of 
the same length and breadth as itself. This is to support and 
steady the knife as it is pushed across the tissue to be cut, while 
the fact of the tissue coming up between the plates allows that part 
of the knife which is to cut the specimen to be kept free of contact 
until it touches the tissue. 
The method of raising the section plate is as follows :—About 2 
inches of accurately-fitting double brass tubing are taken, and into 
the outer one (D) the nut (F) of a fine screw is firmly soldered at 
what is to be its lower end. The inner tube (E) has the section 
plate fixed to its upper end by two screws, with, however, two 
small pieces of vulcanite intervening between the plate and the 
tube, so as to disconnect them as much as possible, and into the 
lower end of the inner tube a transverse bar is fitted, against which 
the screw coming through the outer tube presses when it is desired 
to raise the section plate to which the inner tube is attached. By 
means of a small screw-nail fixing the outer screw to the bar in 
question, the inner can be withdrawn, as well as pushed up when- 
ever that movement is required. A milled head (G) has been sub- 
stituted for the ordinary capstan arms, for turning the main screw 
round. 
The spray points are introduced at the requisite distance below 
the section plate by cutting a narrow slot through both tubes, and 
fixing to the inner one a piece of bent brass, into which the spray 
points can be pushed and held firmly, while a small shoulder on 
the latter prevents them from passing beyond the centre of the 
under surface of the plate. 
Finally, the ether bottle (J) is fastened to the side of one of the 
upright pieces of the framework by a simple hook and eye, the 
hook being fixed to a collar round the neck of the ether bottle, 
and the eye to the side of the framework in question. It will be 
seen, I think, from this description, that with the exception of the 
fine screw for raising the tissue, the details of the mechanism are 
