PHOTOGRAPHIC OUTFIT 9 



they must not come close together near the centre of 

 the top ; if they do, the tripod will never be steady. 



A word or two about plate-holders may not be 

 amiss, as they are of vital importance. Never choose 

 a holder because it is light. The lighter it is the 

 less wood (if it is made of wood) is used, and conse- 

 quently the less strength it has. Scarcely any of the 

 plate-holders on the American market to-day are 

 proof against half an hour of strong sunlight, while 

 with most of them the plate would be hopelessly 

 fogged if the sun shone on the holder for half a 

 minute. Even the slides are not really opaque. If 

 they are made of rubber they become soft in hot 

 weather and brittle when it is cold. The paper 

 slides are better, but they wear out quickly and do 

 not stand dampness. The best kind are made of 

 some preparation of celluloid. These are opaque, 

 withstand any cold, but are apt to become soft while 

 they are hot. Any plate-holder which does not 

 allow of the plate being inserted and removed easily 

 is not to be recommended, as we often have to change 

 plates in the field, when the luxury of a dark room 

 is of course unknown, and when buried in a sleeping- 

 bag on a hot evening, we do not relish having to 

 remove plates from a holder when they insist on 

 sticking ; it is a test too severe for any one*s patience. 



From plate-holders we naturally turn to changing- 

 bags. There are very few kinds on the market (ex- 



