Photography for Naturalists 17 



and of luaiiN' animals renders iieeessarv a \ erv elose approaeli 

 in order to obtain a photogTaph of a ])ra('ti('al si/e, ^Vgainst 

 this elose approaeli the extreme timidity of ])i-aetieally the 

 whole animal ei'eation is an almost insu])eral)le barrier. Thus 

 the use of \erv long-foeus lenses beeomes an absolute 

 neeessit\-. and e\ en with the most powerful a small object 

 like a biixl must be photographed from a Aery few yards, or 

 e\cn feet, and the necessary extension of camera becomes 

 exceedingly cumbrous and awkward at such close quarters, 

 and requires, again, a \ ery heavy and rigid tripod to support 

 the weight. Photographing small birds with a camera between 

 three and four feet long on a big tripod resembles shooting- 

 Snipe with a Maxim-gun. 



Hy using the tele-photo lens, in\'ented a few years ago 

 by Mr. Dallmeyer, a long-focus lens and consequent large 

 image may be obtained without the corresponding increase 

 in the length of camera. 



]5ut this desirable result is only arri\ ed at by a great loss 

 of rapidity. It is necessary to giAC a comparati\'ely slow 

 exposure even with the fastest plates obtainable. The longer 

 the extension of camera the ])igger the magnification, but the 

 greater the loss of rapidity. I find that a short camera with 

 a more nuxlerate magnification gives a gain in rapidity, and 

 improA es the definition and depth of focus, and it is noticeable 

 that my cameras by degrees get shorter and shorter. 



The latest step in this direction consists of a short camera 

 carrying a tele-photo lens, and provided with a reflecting 

 focussing device, which is mounted on a light gun-stock, 



•7 



