320 ROOM FOR DRAWING [Cn. X 



The range of possibility is great, for, by the aid of projection 

 apparatus, one can draw the images produced by the objectives 

 used with the magic lantern, photographic objectives, and micro- 

 scopic objectives of all powers. The microscopic objectives may 

 also be combined with amplifiers or with oculars for projecting the 

 images to be drawn. 



Drawing with projection apparatus has the advantage over 

 drawing with the camera lucida that one can see the entire specimen 

 in one field. More important still, the artist can use both eyes. 

 There is entire freedom of head and eyes, the image remaining 

 constantly in one place, regardless of the position of the draughts- 

 man. 



ROOM FOR DRAWING WITH PROJECTION APPARATUS 



453. Any room suitable for projection is also suitable for 

 drawing with projection apparatus. 



Any laboratory which can be made moderately dark in the 

 day time is suitable for day work; and, of course, any room is 

 suitable in the evening. 



454. Special photographic and drawing room. Many labora- 

 tories have one or more photographic rooms which are also used for 

 drawing. These are mostly separate rooms. Sometimes they are 

 adjoining a laboratory, and sometimes they are like a ticket booth 

 in a large railroad station, i. e., a room within a larger room (fig. 

 179). This is the plan adopted in the Wistar Institute (Anat. 

 Record, 1907) and in the author's laboratory (Proc. Amer. Micr. 

 Soc., 1906, p. 44-45). If these rooms are painted dull black 

 within, stray light is absorbed, and it is much easier to get sharp 

 pictures. In a black room the door can be left partly open and 

 thus secure better ventilation. 



As the radiant gives off much heat it is an advantage to have an 

 electric fan in the room if one works several hours at a time. It 

 is espccialh' necessary in hot weather, summer vacations when 

 teachers have time for research. 



455. A drawing room made with screens or curtains. If one 



has not a permanent room or booth in the laboratory, a fairly good 



