Using a Drop of Water for a Lens 



It Is a wonderful magnifier in microscopic photography 

 By Frank M. Gentry 



EVERY amateur photographer will be 

 glad to learn of a method that is both 

 simple and inexpensive, by which he 

 may make perfectly clear photographs of 

 microscopic objects. 



It has been known 

 ever since the first scien- 

 tific investigations of the 

 refractive properties of 

 different substances, 

 that water, if it could in 

 some practical way be 

 held in shape, would form 

 a lens of extraordinary 

 value. Moreover, it is 

 also well known that a 

 drop of water held by 

 capillary attraction in a 

 loop of wire forms a 

 wonderful magnifying 

 lens. The question, 



therefore, arises, "Why 

 not use this drop of 

 water as a photographic 

 lens?" An explanation 

 of how this might be 

 done follows: 



The first step is to cut 

 a disk A from very 

 thin copper to fit the lens cell of the camera. 

 In the center of this disk, B, there should 

 be bored a 1/32-in. or smaller hole. The 

 smaller the hole is, the more perfect the lens 

 will be and, therefore, the greater its work- 

 ing capacity. The edges of the hole should 



The camera as it is mounted on a 

 pedestal for microscopic photography 



as to remove all the little particles of pro- 

 jecting copper. Great care should be 

 taken to follow accurately these instruc- 

 tions, as the result will depend on your 

 faithfulness in this re- 

 spect. 



Next remove the lens 

 from its cell ; reverse the 

 threaded ring which held 

 it in place; insert the 

 copper disk, and screw 

 in place with the ring. 

 The result may be seen 

 in the illustration on 

 page 125, where C rep- 

 resents the lens cell; D, 

 the threaded ring; E, 

 the copper disk, and F, 

 the drop of water. The 

 cell may now be screwed 

 back into the camera 

 until ready for use. 



In order to place a 

 drop of water in the hole, 

 a wire should be bent as 

 shown at G. Dip the 

 straight end into the 

 water. When it is re- 

 moved, the drop that 

 adheres will be just enough to properly fill 

 the opening. Patience is required to place 

 the drop accurately so that it will not run 

 over the edges, which would be disastrous. 

 The operation may consume over an hour 

 but the results well atone for the trouble. 



then be rubbed carefully on an oilstone so Glycerine or castor oil may be used in place 



At left: Crystalline formation of a bichromate of potassium solution on a gelatine slide. In 

 center: Portions of the antennae of a beetle. At right: Microtomic cross-section <>f a stem of fern 



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