110 ARRANGEMENT OF APPARATUS. 



It will be seen from the foregoing notes the neces- 

 sity for having the laths at the side, marked off in 

 inches and half inches. 



We now proceed to photograph with the one inch 

 objective. The object is supposed to be mounted in 

 fluid, as an illustration of the method to be adopted 

 under these circumstances. 



The microscope being placed on the platform, fig 24, 

 the divisions, nos. 1 and 2, of the stand are rigidly 

 fastened together, by tightly screwing down the 

 board fitting on the bolts projecting from their 

 sides. 



They are then raised till at right angles to no. 3. 

 The camera legs are fastened to the end bolt on no. 

 1, their pointed extremities resting on the ground, 

 maintain this end of the stand in the perpendicular 

 position. 



The horizontal position of the stage is ascertained 

 by a spirit level. 



The tube containing the eyepiece, if not previously 

 attached to the microscope, is now put on ; the ob- 

 jective we wish to use, in this case the one inch, is 

 adapted. 



The substage apparatus, with its condenser and pin 

 hole cap, is fixed in position. 



The lamp previously trimmed and lighted, is 

 placed on no. 3 division of the stand, about ten or 

 twelve inches from the mirror below the condenser. 

 The largest hole of the diaphragm is turned till it 

 occupies a position approximately in the optic axis of 



