202 THE NORTHERN MICROSCOPIST. 
BotreRIL_’s Microscopic Lire Stipe.—The advantages claimed 
for this slide (fig. 37) are the facility with which it can be used and 
Fig. 37. 
cleaned ; its reversibility, allowing either side of the object to be 
examined through thin glass ; the provision for renewing the supply 
of water without disturbing any part of the apparatus, thus enabling 
objects to be kept under examination for an indefinite period ; the 
same arrangement also allowing of the introduction of colouring 
matters, as carmine, indigo, &c. ; and, lastly, its moderate cost and 
durability. 
For Confervze, small Infusoria, &c., it is sufficient to place the 
object on the bottom glass, with a drop of water, and apply the 
covering glass in same manner as when using a glass stage-plate. 
When a thicker layer of water is required, a narrow ring of vul- 
canite, cork, or other suitable material, of the requisite thickness, 
should be placed on the lower glass, and the object put in position, 
and the covering glass applied just as in mounting objects in liquid 
in acell. The supply of water can be maintained by putting a 
drop occasionally in one of the side “wells,” keeping the slide, 
when not under examination, in a small damp chamber, to prevent 
evaporation. ‘To change the water, supply through one “ well,” 
and draw out through the other by means of blotting paper. 
Messrs. Thompson & Capper, of 4, Lord Street, Liverpool, were 
the original makers of this slide, and also of Botterill’s Zoophyte 
Trough, which is illustrated by fig. 22. 
New Lamp.—At a recent meeting of the Bath Microscopical 
Society, Mr. Braham displayed a lamp, which was simply a dimi- 
nutive limelight with a plano-convex lens in front of it, and with a 
rack adjustment, so as to produce from the small pea of light a 
divergent, convergent, or parallel beam. The lamp was also fitted 
to a universal stand, so that like a rod it could be directed out to 
the object, and above and below it in any required position. The 
quantity and intensity of light could be regulated with the greatest 
ease. Mr. Braham stated that the lamp was fed by common coal 
gas, the oxygen gas united with it being pressed through a fine jet 
from a bladder. A bladder of oxygen gas, sufficient for an hour’s 
