THE BEE-KEEPERS* REVIEW 



needed; and the reason is this: That it 

 will give good definition used wide open, 

 thus admitting a great amount of light 

 and allowing of exceedingly short ex- 

 posures. It is often said that one 

 lens is faster than another. It is more 

 rapid simply because it will give good 

 definition with a larger opening, thus 

 admitting more light and shortening the 

 exposure. It is the size of the diaphragm 

 used that governs the length of the 

 exposure, regardless of what lens is 

 used. By using a small opening, the 

 same definition may be secured with a 

 low priced lens as with the more costly 

 anistigmat. 



The anistigmat has, however, another 

 quality, in that the image thrown upon 

 the plate is flat, that is, equally sharp 

 all over the plate, while the image, or 

 focus, of the ordinary rectilinear is 

 saucer-shaped. If the focus is made 

 sharp in the center of the plate the 

 edges are slightly out of focus, and vice 

 versa. As already explained, however, 

 the use of a small diaphragm will bring 

 out good definition all over the plate. 

 By the way, this saucer shape of the 

 image is sometimes really an advantage. 

 It often, I might say, usually, happens 

 that we wish to bring out some object, or 

 portion, of the picture more sharply or 

 distinctly, than the rest of the exposure. 



If we focus sharply on this object, then 

 use the lens wide open, the object is 

 attained. 



If the class of work that you are going 

 to do is such as to allow of time- 

 exposures, that is, one, two, five, or ten 

 seconds, as the case may require, there 

 is no earthly use in paying a big price for 

 a costly anastigmat, as exactly the 

 same results may be obtained with a 

 low priced lens. Simply stop down, and 

 give a longer exposure. Some of the 

 best photographic work that I ever did 

 was accomplished with a single lens 

 (not a doublet) costing only $6. Unless 

 you wish to make exceedingly short 

 exposures, don't waste money on an 

 expensive anastigmat. 



One more point: Don't get what is 

 known as a wide-angle lens, that is, 

 one with an exceedingly short focal 

 length, as it necessitates getting so near 

 the object to be photographed, in order 

 to make the picture large enough, that 

 the perspective is too violent — near ob- 

 jects too large, distant ones too small. 

 Get a lens in which the focal length is at 

 least once and a half the long way of *-he 

 plate to be used— twice the length of the 

 plate would be better. By the focal 

 length is meant the distance from dia- 

 phragm to the plate, when the lens is 

 focused upon some distant object. 



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Selected Articles. 



AND EDITORIAL COMMENTS. 



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GLTTING RID OF FOUL BROOD. 



How to do it Without Drugs, Shaking off 

 the Bees or any Loss of Their Work. 



The only practical time for the suc- 

 cessful treatment of foul brood is during 

 a flow of honey. The most widely known 

 and used plan is that of shaking off the 



bees into a new or clean hive, and al- 

 lowing them to build a new set of combs. 

 The plan that stands next in popu- 

 larity is probably the Baldridge; and, by 

 the way, I have often wondered why it 

 has not come into more general use. 

 Perhaps it appears too complicated, and 

 it is possible that some fear it may not 

 be effectual. 



