ON PHOTO-MICEOGEAPHY. 187 



constructed to take wet plates as well as dry. 

 Unless a very large camera or a very small micro- 

 scope is used, the camera will probably want block- 

 ing up to bring its centre exactly to the same height 

 as the optic axis of the microscope. For this pur- 

 pose a light support of pine should be constructed. 

 It should be as long as the camera when fully 

 extended, and should be graduated in inches along 

 one edge. If polished it will keep cleaner and look 

 much better than if left plain, and will not wear 

 the edges of the bellows. On the top of this 

 support the two ends of the camera may be made 

 to slide, and may be secured in any position by set 

 screws running in a central groove. 



The microscope, camera, illuminating apparatus, 

 &c., are to be clamped down in marked positions 

 on a base board, about 6 feet long, 11 inches wide, 

 and 1 inch thick. The point of the base board, 

 immediately below the position of the object when 

 in use, should be marked, and the board should be 

 graduated in inches from this point in both direc- 

 tions. The camera support should have a play of 

 five or six inches to, or from the microscope, and 

 when adjusted, should be clamped by a single turn 

 of each of two screws, which hold it to the base 

 board. To meet the wants of those who are 

 content to use the eye-piece, Mr. Stanley, of London 

 Bridge, has constructed a cheap apparatus, con- 

 sisting of an ordinary J plate bellows-camera, and 

 a base board, to carry microscope and lamp, and 

 with adjustable platform to bring the camera up to 

 the height of any ordinary microscope. 1 



1 Mr. Stanley also publishes a pamphlet, containing instruc- 

 tions for working dry plates, silver printing, &c., which is 

 worthy the attention of beginners. 



