22 ELEMENTARY PHOTO-MICROGRAPHY. 



Consequently, for the purpose of this book, 

 a special room, with massive foundations, in 

 a special district free from the vibration of 

 passing vehicular traffic, monochromatic and 

 electric or limelight, the heliostat for sunlight, 

 expensive apochromatic lenses, or even specially- 

 corrected microscope objectives, will not be re- 

 quisitioned for carrying out any of the instructions 

 hereinafter given, but only such simple apparatus 

 as the ordinary photographer possesses, with the 

 addition of a microscope. Indeed, for low power 

 work, a camera, a paraffin lamp or lantern, and a 

 few home-made articles are all that are essential, 

 no microscope being required, as the operation is 

 one of simple enlargement. 



The adaptability of a quarter-plate camera for 

 all purposes may be seen from the fact that any- 

 thing from the smallest bacteria, or the most 

 difficult test diatom, to a five-shilling piece, in 

 fact anything within the range of a microscope, 

 may be taken with a camera extension varying" 

 from 3in. to loin. 



Moreover, it is desirable that the worker 

 should have the whole of his apparatus within 

 easy reach during the operations of centring, 

 illuminating, and focussing the specimen without 

 change of position, and with long camera extension 

 this is not possible. 



