390 



PHOTOGRAPHING MINCJTE OBJECTS 



graph. Very little, so far as I can see, has been said about them ; 

 I allude more particularly to the eggs of the various parasites, the 

 coarser foraminifera, scales on the wings of beetles in situ. Now, 

 these are more difficult to do, and some of the best work in this 

 way I have seen has been done by my friend Mr. Evans, and I 

 think — in fact, I know — they are not to be equalled. I candidly 

 confess I cannot do them nearly so well. A few of my attempts 

 I will show you. As all the light we have to deal with is that 

 which is reflected from the object itself, it is absolutely necessary 

 to concentrate all the light possible on the object. There are 

 several ways of doing this, but first of all your object must be 

 mounted very flat, and in the centre of a small black disc, so as 

 to allow the light to pass round the object from your condenser. 



The Stomach Bones of Brittle Star Fish. 



This light then falls upon a silvered reflector or Lieberkuhn 

 mounted on the objective, the curve of which must be equal to or 

 a little longer in focus than the objective, so that when the object 

 is in focus, a small amount of collar adjustment enables you to 

 focus down and adjust the rays of light that have been received 

 upon the silvered surface of your reflector. Of course, the more 



