58 NOTES AND MEMOEANDA. [^Jo\rnTjaaSXiS^ 
subjoined description of my lamp, I have endeavoured to make it 
a practical realization of Sir David's ideas on artificial illumination. 
A. A small brass tripod foot sufficiently heavy to keep the lamp 
steady and in any position, and so formed as to take up very little room 
on the table and not to be in the way of the stand of the microscope. 
B. A cup-and-ball joint moving stifSy and keeping the lamp quite 
firm at any angle, and so constructed that it cannot be inclined at a 
greater angle than the lamp will burn steady and clear. 
C. Rack-and-pinion motion extending to 12 inches, so that the 
light can be directed upon the stage of the largest microscope for 
opaque objects. 
D. A short arm projecting from the lamp carrying a sliding-tube, 
which carries either a Rainey's Light Modifier or a concave reflector 
of plaster of Paris, giving a pure white cloud light when examining 
such objects as bone and wood sections. 
E. Condensing lens, with sliding-arm and clamping-screw. 
F. White opal glass reservoir in revolving collar, holding a 
sufficient supply of paraffin for seven hours' consumption. 
G. Metallic shade chimney with white lining, fitted with movable 
cell, holding a disc of thin glass, forming a perfect shade to the eyes, 
and condensing the light in one direction, thereby doing away with 
the great objection to all lamps hitherto constructed, that of broken 
chimneys. The drawings show the lamp in two positions, one for 
illuminating the mirror of the microscope, and the other for illumi- 
nating the achromatic condenser when using high power objectives, 
thus obtaining direct light from the lamp and still keeping the 
microscope at a convenient angle for vision. 
This lamp I find most effective in illuminating any portion of an 
aquarium, as it will concentrate a cone of light through any portion 
of the tank. For the micro-spectroscope it is most invaluable, and 
with the present range of rack-motion it will be found of advantage to 
the surgeon in using the opthalmoscope or larynxscope. 
I cannot conclude this notice without tendering to Mr. Thomas 
Eoss my best thanks for the assistance he has given me, and also the 
perfect manner in which he has carried out my ideas in the manu- 
facture of the lamp. 
Eoss' Hew Microscopic Vice, with stag^e forceps, of which we annex 
a diagram, is a very handy accessory, as, in addition to the usual light 
spring points A, for holding any delicate minute fibre or piece of 
tissue, it has, at its other end, a pair of small jaws B, which by means 
of a milled edge G at the end of the tube sliding through the ball and 
socket-joint D, can be separated » with the greatest precision to any 
extent up to an inch, and will be found very useful for holding 
various solid objects whose faces are irregular or not parallel with 
one another, by enabling the observer to bring any face of the object 
under view with the greatest facility. 
