BIRD-WORK FOR INDOORS 233 



They are set face to face, with one ordinary photo- 

 graphic lens between them to make the image, and 

 a dark cloth thrown over the junction to keep out 

 extra rays. The ground glass is removed from the 

 front camera and the negative inserted in its place, 

 or set close in front if it be of larger size and only 

 a part of it is needed to enlarge. Then it is simply a 

 matter of adjusting the bellows. For enlarging, the 

 front bellows is short and the rear one long, and vice 

 versa for reductions to make lantern slides. After 

 securing a sharp focus, the plate-holder is inserted in 

 the rear camera and an exposure made by the bulb. 



The same rapid plates may be used as afield, if 

 more convenient, but I advise securing a slower grade, 

 which are easier for the inexperienced to handle. 

 With the latter, with the lens wide open, a usual in- 

 terval for exposure with a normal good, rather 

 plucky negative, would be about two seconds against 

 a bright sky, and more according to the light. Over- 

 exposure will make a flat, gray picture, not as good 

 as the original. 



This process secures a positive. After that is de- 

 veloped, fixed, and dried, some evening a contact nega- 

 tive must be printed from it. Simply put the posi- 

 tive in a printing frame, film side up, and lay a plate 

 upon it, the sensitized sides in contact. Expose this 

 to a white light, a foot away, for a short interval and 

 develop. The time must be found by test, according 

 to the light used. One or two seconds is usually 

 enough one foot from an ordinary kerosene lamp or 



