;186 REPORT OF NATIONAL MUSEUM, 1892. 



subject may be a bird, its young, or its nest, <>r a dissection of a bird, or its skele- 

 ton, or its eggs, aud so on indefinitely. Owls present to many artists difficult sub- 

 jects to draw satisfactorily, but there is no reason why we should not, by the aid of 

 the camera and a 5-by-8 plate, for a small sum, and in very short older, have ready 

 for the lithographer a life-size figure, aud a perfectly accurate one, of such a species 

 as Nyctala acadica, or upon a similar plate a handsomely reduced figure of Bubo vir- 

 ginianus. Again, by varying our material, colored figures are easily obtained for 

 like purposes. Photographs of this character may also be used to make wood cuts 

 from, or they may be reproduced by some of the various styles of "process work." 

 Yet another object: We may desire to produce by the aid of a camera an accurate 

 figure of any of the above-mentioned subjects from which an electrotype can be 

 directly made. This also is now easy of accomplishment, and such illustrations 

 meet avast variety of needs in descriptive ornithology. These, then, are some of 

 the principal objects to be attained, viz, clear, accurate figures, either life size or 

 reduced to any desired size, and either plain or colored, which (by the use of differ- 

 ent materials) can be used at once by either the lithographer, the wood engraver, 

 the "process worker," or the electrotyper. 



Your material must be the best in all particulars. I use a large, first-class, quick- 

 working lens; a Blair's camera for the 5 by S plate; the iron and oxalate, developer, 

 using the chemically pure material (filtered); bichloride of mercury and ammonia 

 for intensifying, etc. 



Our method of procedure can best be illustrated by a few examples. Say we wish 

 to reproduce, life size, a hawk's egg. Suspend on the wall opposite and under the 

 strong sunlight, a smooth, half-inch pine board; cover this with white blotting 

 paper, held on with some half dozen artists' thumb tacks. Of course your egg is to 

 be blown and not show the opening. Next you decide whether or no you desire it 

 to throw a shadow; if you do, you simply fasten it to the blotting paper with a 

 small piece of soft wax, exposing to the camera the side you wish represented ; if you 

 do not, you insert a piece of wire a few inches long into the board and perpendicular 

 to it, and fasten the egg to the end of it with a soft piece of wax. Place a bucket 

 of water on the floor under the egg, in case the specimen should accidentally drop 

 off. Focus the egg natural size and sharp on the ground glass of your camera; this 

 maybe ascertained by a pair of calipers, comparing the actual length of the egg 

 with its image upon the ground glass. Insert your smallest diaphragm and expose, 

 the time of exposure being governed by your former experiences. I prefer Seed's 

 dry plates. They give excellent results. After developing, unless you get a very 

 strong negative it is always best to intensity your plate, and this is done by the 

 usual mercury and ammonia process. Now, if you wish an un colored figure to be 

 lithographed, or woodcut, or for some of the special processes, you must print on the 

 best ready sensitized albumen paper, toning the print handsomely afterwards. On 

 the other hand, if you desire a colored figure, you must print on plain, i. e., non- 

 albumenized, sensitized paper, and afterwards color the print by hand with New- 

 ton's water-colors from the specimen. Pure white eggs stand out well when pho- 

 tographed against black velvet or crape; this also applies to some skulls and other 

 osteological specimens, when they are cleaned to a state of glistening whiteness. 

 Such a procedure defines the outlines well for the engraver. 



When we conic to the photographing of birds, living birds, for the purpose of 

 obtaining the proper kind of figures that can be used for the various methods of 

 reproduction now in vogue, we enter upon a field where one ran display no end of 

 patience, tact, and ingenuity. It will be a long day before the writer will forget 

 his experience in obtaining a photograph of a live screech owl. Three times I 

 walked half a mile from the house where 1 could get a sky background tor him on 

 the summit of a hill, where an old natural stump was also to be found to serve as a 

 perch for him. Just as good a result can be obtained by photographing your bird" 

 in your studio with a sheet for a background, and then you may choose any kind of 



