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best text-books, and being methodical and, above all, cleanly. 
In conclusion, it may be of interest in this connection, to 
know as to who took the first photomicrographs. This 
question, I think, is answered by the following extract which 
I have thought of sufficient interest to microscopists to 
transcribe and register here. In the Journal of the American 
Institute for 1840, I find some interesting letters from Paris, 
written by Prof. Morse, detailing the then new and wonder- 
ous discovery of Daguerre, by means of which he was 
enabled to fix the sun-beam, and make it take pictures of 
still and moving objects. On page 409 he says: 
“One of Mr. D.’s plates is an impression of a spider. The 
spider was no bigger than the head of a large pin; but the 
image magnified by the solar microscope to the size of the 
palm of the hand, having been impressed on the plate, and 
examined through a lens, was further magnified, and showed 
a minuteness of organization hitherto not seen to exist. 
You perceive how this discovery is, therefore, about to open 
a new field of research in the depths of microscopic nature. 
We are soon to see if the minute has discoverable limits. 
The naturalist is to have a new kingdom to explore, as much 
beyond the microscope, as the microscope is beyond the naked 
eye.” This letter is dated March 9, 1839, therefore it seems 
that Daguerre was the first to take enlarged pictures of 
objects of natural history, by means of the action of sunlight 
upon Salts of Silver. 
Prof. Edwards’ paper was fully illustrated by means of the 
various apparatus used, and a large series of Photomicro- 
graphs taken by Drs. Woodward and Curtis, at Washington, 
and himself: 
At the same time he exhibited a series of specimens of 
what had been erroneously termed Photolithographs and 
Photoengravings. These were prints obtained by the action 
sunlight, but in permanent pigment instead of Silver as in 
the ordinary Photographs. The best and greater number of 
these were produced by the process invented, and now being 
worked to a very considerable extent, and very successfully, 
by Mr. G. G. Rockwood, of this city. The Woodbury 
