APPARATUS AND GENERAL ADVICE. 5 



the shorter the tubing the quicker and more 

 certain the exposure. 



It is better to carry half a dozen dark slides 

 already charged with plates than to risk re- 

 charging two or three in a changing bag, unless the 

 photographer has a friend who will accompany him 

 upon his expeditions and assist in the somewhat 

 tedious operation. Even then it is necessary to use 

 the greatest care, as a very tiny ray of light will fog 

 a rapid plate and utterly ruin the picture of a lifetime. 



When away on our summer holidays, which we 

 generally take in remote parts of the country, we carry 

 our developing materials with us, and prefer papier- 

 mache trays to porcelain ones, as they are much lighter 

 to take about and less likely to suffer damage at the 

 hands of railway porters. A green-baize focussing cloth, 

 slightly larger than the red-and-black ones supplied 

 by dealers in photographic outfits, is a very necessary 

 article for use in natural-history work, especially where 

 the camera has to be hidden and the plate exposed 

 from a distance by the aid of the long pneumatic 

 tube. We have a cloth of this description con- 

 stantly in use, and have loaded each of its four 

 corners with a charge of shot, so as to prevent 

 them from flapping about in a breeze. A few 

 safety-pins will be found very useful for fastening 

 the cloth over the camera. 



Some of the chief things to be remembered 

 when out in the fields are, so far as apparatus is 

 concerned, to have the lens perfectly clean ; no 



