252 THE OPEN BOOK OF NATURE 
secure photographs of objects as they appear under 
the microscope. Such pictures are called “ photo- 
micrographs,” and the process of taking them is 
designated “ photo-micrography.” The process is 
not so difficult as it may seem to some of you. I 
took photo-micrographs when I was thirteen years 
of age. The lens of the camera is removed, the 
microscope placed in a horizontal position, with the 
end of the tube containing the eyepiece inserted 
into the hole in the front of the camera. Light is 
focussed upon the object, the connection between 
camera and microscope being made light-tight. The 
image is projected on to the camera screen and 
focussed. Then a dark slide is inserted and an 
exposure made. Exposures vary according to in- 
tensity of light, density of object, and the magni- 
fication ; they are generally long. There are several 
reproductions of photo-micrographs among the 
illustrations of this book; all the pictures were 
obtained by the simple method I have just outlined, 
the apparatus being conveniently arranged on the 
board I use for flower photography and copying 
(p. 247). My exposures varied from thirty to sixty 
seconds, electric light being used. 
Finally, let me insist upon the necessity of keeping 
the fullest possible Nature records, especially of 
observations made in your own localities. It seems 
trivial to note a lark singing on April 1, or the 
appearance of a Spotted Orchis in June, but even 
the most trifling observations have their value. If 
you hear birds or see plants in advance of their 
usual seasons, you may be sure that such pheno- 
mena have their special causes. So full should your 
