156 W. M. GRAHAM—THE PHOTOGRAPHY OF DIPTERA. 
As soon as the insect is sufficiently dry it is ready to be photographed, and for 
this purpose must be transferred from the dise of cardboard to the glass support 
already described. To do this, take the easel and introduce the glass support into 
the grooves so that the hole in the glass plate filled with cork is in the middle of 
the square opening in the easel. Then take a pin of the same size as that in the 
insect you are about to transfer from the cardboard disc and push it gently 
through the centre of the piece of cork cemented in the glass support. This will 
render easy the subsequent introduction of the sharpened end of the pin bearing 
the insect. Now remove the paper supports, take the disc bearing the insect 
between the fingers and thumb and gently push up the pin from beneath until it 
can be grasped by a curved forceps introduced between the insect and the dise. 
Holding the pin thus grasped in the forceps, draw off the disc, and introduce the 
sharpened end of the pin into the pinhole already made in the piece of cork in the 
glass support. Then from the back draw the pin through, until the legs of the 
insect are in contact with the glass plate, the head of the insect being so placed 
that it will be directed downwards when the easel is clamped in position on the 
base-board. 
Now clamp the easel in position and arrange the millimetre scale above the 
insect, in the same vertical plane, and near enough to the insect to be included in 
the picture on the ground-glass. In the absence of the slide for the purpose, 
this can be effected by pushing a long pin through the wooden rod attached to 
the scale and pinning it to the wooden easel. 
ILLUMINATION. 
The lighting is effected in the following manner. The whole apparatus, 
arranged according to the above directions, is placed upon a table either in front 
of, and parallel with, a well lighted window, or in an open verandah where it will 
be sheltered from the wind. On the table behind the easel is placed a large 
reflector formed of a drawing-board with a sheet of white Bristol board pinned 
upon it (fig. 2). This reflector is to be inclined at such an angle as will secure 
uniform lighting of the whole of the opening in the easel. The amount of light 
from the reflector can be regulated by varying the distance of the reflector from 
the easel. 
On the base-board, immediately in front of the easel, is placed a small square 
glass mirror (5” by 5”) inclined at such an angle as will light the insect on the 
easel uniformly from below. Care should be taken that the reflection of the 
edge of this mirror is not included in the picture on the ground-glass, and that 
sharply defined clouds are not reflected. 
On the table on the left-hand side of the base-board, and slightly in front of 
the easel, is placed a shaving mirror upon its stand. The mirror should be raised 
slightly above the head of the insect and inclined at such an angle as will secure 
the uniform lighting of the left side of the insect by light reflected from the 
mirror. 
The object of the plate of glass, here used as a support, is to avoid the heavy 
shadows which would be cast by the body, legs and wings, of the insect upon an 
opaque support. The object of the white reflector behind the easel is to furnish 
