HOW TO MAKE VIVARIA. 13 
desired to take the case to pieces) at each corner of that frame 
which is chosen for the bottom, and then the opposite ends of 
the zine should be fastened similarly to the other frame. 
A sheet of finely perforated zinc ought to be 
nailed over the inside of the bottom frame, running 
as closely as possible to the grooves prepared for the 
glass. The glass sides are put in their places be- 
fore the pillars are fastened to the upper frame. 
The glass side in front may be made to slide up; 
for this purpose the groove in the upper frame should 
be cut quite through, and in order that the glass 
may the more readily be lifted, it ought to be so 
broad that its upper edge will stand din. above the 
frame at the top. The sliding side is convenient when 
the case has to be provided with fresh sand or gravel, 
z oP AX™ and it also will keep the wooden drawer in its place. 
PILLAR FOR At ¥, Fig. 3, there are narrow strips of wood to 
VIVARIUM - 
SHOWN aT prevent spaces being left between the edges of the 
wo drawer and the sides of the case. These strips 
need be no deeper than the drawer, and the 
latter should be made to fit quite closely to them. If zine is 
used for the pillars, the glass sides may be fastened in their 
places by means of the following cement: One part each of 
plaster of Paris, litharge, and fine white sand, and one-third 
part of finely-powdered resin. These ingredients should be well 
mixed into a putty with boiled oil and driers. Cement, how- 
ever, must not be employed if it should be wished at any time to 
take the case to pieces. Instead of the cement, four narrow 
pieces of wood, one for each corner, about 3in. by $in., running 
from the top frame to the bottom and fastened at both ends by 
screws passed through the frames, can be used. These, if placed 
quite in the corners, will hold the glass very firmly. The out- 
side edges of the frames, if the pillars are of zinc, may be covered 
with narrow strips of the same metal. When zinc pillars are 
used no grooves need be made in the upper and lower frames 
for the glass sides. 
As arule, the inmates of a Vivarium should be attended to 
from the top, and for this purpose the case ought to be provided 
