APRIL — SEPT. 1859.] ef Microscopic objects. 



15 



tain, I think you will agree with me that it does not seem neces- 

 sary to meddle with that part of the instrument. 



The latest writer upon this subject, Mr. J. R. Traes, has not, I 

 think, added anything of value to our previous store of knowledge. 

 The most remarkable thing in his paper is his great dislike to one 

 of the most valuable adjuncts to a Microscope, viz., a mechanical 

 stage, and his appropriation, without acknowledgment, of Mr. 

 Highley's mode of applying the object glass stage and mirror to 

 the Camera. 



Having alluded, as briefly as the subject admitted, to what has 

 been done by others, I will now proceed to describe, as well as I 

 can, my method of working with the compound Microscope and 

 an ordinary Photographic Camera, for which the only additional 

 apparatus required is the following : 



1st. A board,* 3 feet 6 inches long, 1 foot wide and 6 inches 

 thick, has at one end a strip of wood nailed (or screwed) on at 

 each side, so as to allow the foot-board, with which most Micros- 

 copes in upright cabinets are supplied, to slide easily between 

 them, but without any lateral play. This preserves the true 

 direction of the axis of the Microscope, the prolongation of which, 

 when the body of the instrument is horizontal, should pass per- 

 pendicularly through the centre of the focusing screen. The 

 requisite altitude is given to the Camera by erecting at the other 

 end of the board a table on four legs, which are to be secured, 

 by mortising, to the board. The table should be as much larger 

 than the bottom of the Camera as will permit a beading half an 

 inch high to be screwed on all round ; the Camera fits tightly 

 within the beading and is thus prevented from moving. Such a 

 board as the above cost me 5 Rupees. 



2nd. A cylinder of black cotton velvet, doubled for greater 

 security, somewhat larger in diameter than the flange of the 

 Camera lens, and from 4 to 6 inches long. The flange is unscrew- 

 ed and loosened sufficiently to tuck one end of the cylinder well 

 in between it and the front of the Camera, the flange is then 

 screwed up tight again, the screws passing through the velvet. 



* The size of the board will depend upon the size of the Camera 

 and Microscope. 



