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METHOD OF MAKING PHOTO-MICROGRAPHS OF MOSSES 
AND HEPATICS. 
William B, Davis. 
(Abstract of Talk given at Sullivant Moss Society Meeting, Baltimore, 1908.) 
To the unitiated photo-micrography seems to belong to the realms of 
mystery and difficulty. It is safe to assume that the majority of bryologists 
are amateur photographers, and use a compound microscope in their work. 
The reason that this form of work is not more common arises no doubt from 
fancied rather than real obstacles. The paraphernalia and manipulation 
required are both simple and easy. While it is not given to all of us to have 
sufficient artistic ability to produce creditable reproductions of what we see, 
yet the poorest sort of a carpenter can build the necessary outfit for this 
work. Again some of our drawings are apt to be colored with what we think 
we see. Given a fairly transparent section or mount (as most preparations of 
the mosses and hepatics are), a coal-oil lamp, compound microscope, and plate 
camera, we can at least have the experience of something novel. Nor is the 
possession of a suitable camera a sine qua non. Obtain a plate holder and 
build your camera somewhat after the plan of the man who carried the bung- 
hole to the cooper’s shop to have a barrel made for it. The camera lens is 
not used in this work. 
Take a small wooden box, or glue one together from stiff cardboard ; 
blacken it on the inside; cut a hole in the front, and through the hole push a 
cone shaped like a megaphone. The architects’ ingenuity will suggesta way 
to hold the ground glass and plate holder at the other end. Make the box 
perfectly light tight. 
To take the photograph bend the microscope over to a horizontal position. 
Lower or raise the lamp on some books with lamp in front of the microscope, 
edge of flame towards the microscope and in line with the optic axis ; swing 
the mirror out of the way; place the object (transparent of course) under the 
spring clips. Have the camera box on a level with the microscope and push 
the small end of the cone over the tube of the microscope, the eye piece 
remaining on, if the home made affair is used. 
If using a plate camera, remove the lens and push the tube into the 
camera. By focusing, the clear image of the object will be seen on the 
ground glass. Some folds of dark cloth should be wrapped about the tube 
where inserted into the camera in order to keep out all light. After the 
sharp image has been obtained, care must be exercised by pressing firmly 
with one hand to make sure that the apparatus is not disturbed while insert- 
ing the plate holder. 
Exposure by lamp light will require considerable time, perhaps some 
minutes, and experience at this stage will be the best guide. Opaque objects 
can be best photographed by using ordinary daylight. 
Philadelphia, Pa. 
