METHODS OF RESEARCH! APPARATUS 97 



developing is done under a red (bulb) drop light near the sink. 

 There is a door at either end (both opening inward) : one gives 

 entrance from the bright photographic room, the other from the 

 rather dark central corridor of the building. Both should be 

 hinged on the side nearest to the developing table. The size 

 of this ante-room is 5 feet 8 inches by 9 feet. 



The dark-room proper takes the remainder of the space (9 

 feet 4 inches by 9 feet), but one corner of it is occupied by the 

 labyrinth so that the actual working space is considerably 

 reduced. The labyrinth (2 feet wide) begins in the northeast 

 corner of the ante-room next the door opening into the dark 

 corridor. As an additional precaution against the accidental 

 entrance of light, this corridor door is provided with a push 

 lock to be used whenever necessary. On the right-hand side, 

 as one enters the dark-room proper, behind the south wall of the 

 labyrinth, is a narrow space occupied its whole length on one side 

 (the north side) by the loading shelf. On the east wall, facing 

 the observer as he enters the dark-room, is the developing shelf. 

 At his left against the north (corridor) wall is the fixing shelf 

 and in the angle between the two shelves is the deep sink (36 

 inches long by 20 inches wide). The dark-room consists, 

 therefore, of two rectangles, the larger 5 by 9 feet occupied on 

 the outer (east) side by the long developing shelf and the sink 

 just referred to; and at one end (the north) by the shorter fixing 

 shelf, and at the other (south) end opening into the smaller 

 rectangle (3 feet 10 inches long by 3 feet wide) which is occupied, 

 as already stated, by the loading shelf. This abuts against the 

 labyrinth wall, and above and below it are other shelves for the 

 storage of boxes of dry plates and plate holders. There are also 

 shelves under the developing shelf for extra trays, and under and 

 above the fixing shelf. 



Two persons can develop in this dark-room without inter- 

 ference and the loading shelf is also long enough to allow two 

 persons to use it at the same time. There is, however, no waste 

 space and everything is within convenient reach. A step or two 

 brings you to any part of the room. 



The subdued light by means of which exposures must be 

 developed may be sunlight or electric light, passed through a 



