The University Micro-Projector. 
For micro-projection on a sufficiently large scale for class purposes, including work with 
high powers, a very rigid construction is essential and a powerful source of light must be employed 
to enable a critically defined and brilliant picture to be shown. If an apparatus is employed 
consisting of a separate microscope and illuminating apparatus, it is practically impossible to 
keep the various parts in continuous adjustment, and to be convenient and satisfactory in] use 
such an apparatus should be made in a complete unit to ensure its stability. 
No, 4954 
The general design of this projector can be seen from the illustration—and it will be seen 
that the whole of the parts are carried on a heavy casting which gives it the necessary solidity. 
The illuminant is an arc lamp which is enclosed in a well ventilated lamp-house with a large door 
on one side to allow of access to the arc lamp. The light is concentrated by means of a condenser 
fitted to the front of the lamp-house and is then passed through a cooling trough to the substage 
condenser on the microscope. This condenser consists of an optical system for use with low 
powers, and above it, fitting in a slide in the stage, is a second optical system which, when slid 
into position above the low power condenser, renders it suitable for high powers. An iris 
diaphragm and a focussing adjustment are provided to the condenser. From this condenser 
the light is passed through the specimen and through the microscope object glass and eyepiece 
and projected on to the screen. 
The microscope itself has all necessary adjustments including coarse and fine focussing 
adjustments. Standard object glasses and eyepieces are used. The object glasses can be fitted 
into a double or triple revolving nosepiece. The microscope is hinged so that it can be used either 
horizontal or vertical. For ordinary objects it is used in its horizontal position, but where objects 
in fluids are being examined, it is placed in its vertical position. A mirror is then fitted below the 
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