1900] MICROSCOPICAL JOURNAL. 311 



cameras to their stands. These screw into bosses set into 

 the baseboard at intervals of 4 in. apart. The baseboard 

 supports a i-plate camera, which, when closed, measures 

 6 in. high by 5-f in. wide by 7 in. long, having leather bel- 

 lows capable of 2 ft. 6 in. extension. 



The front of the camera is provided with a spiral rack 

 and a pinion, having 6 in. traverse, and the back part of 

 the camera can be pulled out and clamped at any desired 

 distance by means of the clamping-screw. A grooved 

 double reversible focussing screen, 10J in. by 4J in, hav- 

 ing tine ground glass in one window, and clear plate glass 

 in the other, fits the camera-back, and is in correct reg- 

 ister with the plates contained in the double-dark slides, 

 the clear glass pane bein^- useful for delicate focussing 

 with a magnifier. 



The camera is provided with several fronts, which are 

 interchangeable. One takes a 5in. focus Groerz lens, an- 

 other a 3in. focus Cooke's lens, and a third, furnishad with 

 the R.M. Society's thread, takes Planar lenses, Zeiss's 

 projection apochromatics, or any other desired objective. 

 The latter front is also provided with a simple form of 

 exposure shutter. Another front, also provided with an 

 exposure shutter, has in its centre a light-tight cap, for 

 use with accessory apparatus for medium and high-power 

 work, to be hereafter described. A rotating stage, of sim. 

 pie construction, with brass clips, is carried upon a base- 

 board having a slot in its centre and a clamping-screw. 



This stage can be brought up to any desired distance 

 from the lens employed upon the camera-front, and se- 

 curely clamped. Behind the stage there is ample space 

 for any condensing lenses, colored-glass screens, heat-fil- 

 ter, limelight jet, or any required apparatus. The appa- 

 ratus thus set up is available for copying or reducing, or 

 for any low-power photo-micrography according to the 

 lens employed. 



For photographing large insects or other large objects, 



