42 Cincinnate Society of Natural Fiistory. 
To the subject of development there seems to be no limit; not 
so, however, with the subject of a dark room ; with the former much 
is to be taken on faith, to be accepted or rejected as the circum- 
stances afterward seem to warrant; but with the latter it is open 
as the air, and with a very small modicum of common sense, and 
at an equally small expense, a dark room may be constructed 
which will answer every purpose of the amateur. Some of the 
best negatives I have ever made were developed on the banks of 
a river with no shelter above my head, nothing but a barrel stave 
laid across a couple of logs for a table, and an ordinary lantern 
covered with ruby fabric or yellow post-office paper for my lght 
—the light which escaped from the top of the lantern extending 
upward and doing no harm, as there was nothing to reflect it back 
again upon the plate. Of course, a dark room can be constructed 
having all the modern conveniences for washing, etc. But the 
requisites are not many, consisting mainly of non-actinic light, 
and an unlimited supply of cold, clear water. The term ‘‘ dark 
room’’ does not necessarily mean a room totally dark by any 
means; it may be far from dark, only let the light which comes 
in be of a low actinic character. Of course, no light is absolutely 
non-actinic, but the actinic rays may be so nearly eliminated as to 
render the light practically harmless, and yet the room may be so 
light that objects can be distinctly seen. If one can arrange it so 
that the light can enter from the outside, it is very much better 
than to have a lantern in the room where you are at work. This 
is especially the case if your room is small and the ventilation 
poor. My own dark room, which is in the cellar, is six feet long 
and three and a half feet wide, and although I have any number 
of bottles, boxes, etc., I find it plenty large enough for one person 
to work in comfortably. From the outside of the house I have a 
two-inch iron pipe leading to one lower corner of the room, while 
at the diagonally opposite upper corner a pipe of the same size is 
connected with the smoke flue of my furnace. ‘This insures me at 
all times a perfect ventilation. My light is from a gas jet from the 
outside of my window, but reguiated from within by a key, so I 
can have any desired amount of light in a moment without going 
out of my room or opening a window. In so small a room space 
must be economized, and this can be done, and all the shelf room 
desired can be had, by having such shelves as are constantly in use 
above the height of one’s head, and those not constantly in use 
