1526 



Journal of Applied Microscopy 



The movable stage is also controlled from the ground glass six feet away by brass 

 rods with milled heads and cord and pulley attachment (/), and the stage is sup- 

 ported against the strain of these by an adjustable brass pillar (g-). The stage 

 can thus easily and quickly be searched over a space three-eighths of an inch 

 square. The course adjustment of the microscope is similarly controlled. 



Some may think that these arrangements are mere conveniences ; they are, 

 however, indispensable, for the reason that without them photomicrography 

 ranging in powers from 5 to 5000 diameters consumes so much time that the 

 game is not worth the ammunition. 



Fk;. 2. — Photomicrograph of a starfish, fixed and decalcified in picro-sulpliuric acid, and, after washing, stained in 

 acid carmine. A 35 mm. apocliromatic gave the necessary resohition and depth of focus, and a camera extension 

 of four feet gave a magnification of forty diameters determined by measuring the object and the image. 



The arrangement for controlling, from the ground glass, the coarse adjust- 

 ment — necessary in low power work ; that for controlling the stage — so conven- 

 ient as to be necessary in all classes of work; the adjustable pillars under the 

 microscope bench ; the adjustable pillar under the microscope to offset the pull 

 of the cord on the fine adjustment screw ; the adjustable pillar under the stage, 

 and such a scale on both the camera table and the optical bench that all parts 

 of the apparatus can quickly be brought into any desired relationship, are addi- 

 tions which we have made to the apparatus since setting it up. 



When work of all powers is to be done on the same instrument, two features 



