40 



Bird- Lore 



FIG. 3. VIEW OP HOOD (OPENED) FOR 

 GROUND GLASS OF MIRROR CAMERA 



Just as the mirror closes upon the bed (O, O) the end of the 

 lever (H) is forced upwards, the catch at E holding the cog on 

 the upper roller is released, and the slot in the curtain passes down- 

 wards across the plate and makes the exposure. The ground glass 

 (K, K) is protected with a four-sided pyramidal hood (Fig. 2, P) 

 with a slot in the top to look through (Fig. 3, A). This shuts out 

 , all the light from above and' gives 



the operator a good opportunity to 

 focus sharply upon the ground glass 

 inside. When not in use the four 

 sides, being hinged at their bases, 

 fold down upon the ground glass 

 and are out of the way. 



The bottom of the box is pro- 

 vided with a nut for the reception 

 of a tripod screw, and the curtain, 

 when rolled up as far as it will go, 

 rolls entirely out of the way. The 

 mirror may then be raised and held 

 there by means of a small sliding 

 attachment to hold down the spur 

 of the lever at M, Fig. 2 ; and the 

 box may be used as an ordinary camera by operating a shutter at- 

 tached to the front of the lens. 



This camera thus contains all 

 hand camera, with the additional 

 and focusing attachment. 



To make a shot the camera is held in the hands and the image 

 is focused sharply upon the ground glass. The curtain is already 

 rolled up and the slide drawn from the plate-holder. The plate is 

 in no danger of being light-struck from within, as it is protected by 

 the light-proof curtain. The spur of the lever projecting through 

 the side of the box (M, Fig. 2) is simply pressed downwards with 

 the thumb, the mirror raises out of the way of direct communication 

 between the lens and the plate, and just as it closes upon the light- 

 tight bed at the top, the curtain drops and the slot, passing across 

 the face of the plate, makes the exposure. 



Thus far I have used this camera largely upon animals, but as 

 an illustration of its effectiveness on birds I may describe the 

 manner in which the accompanying picture of Wild Geese (see 

 frontispiece) was made. 



These birds, although in one of the ponds of Central Park, New 

 York City, are by no means tame, and a close approach to them is 



the advantages of the ordinary 

 features of the full-sized finder 



