In the laboratory we visit first the developing-room, feeling our way cautiously into the dark around many corners that cut off every possible ray of light from outside. Walking on wet slats we reach at last the chamber in the middle of what seems to be an almost impenetrable labyrinth, and in the dim red light can barely make out the vats where the strips of celluloid, wound back and forth on wooden hand-racks, are being dipped into the developer. Nowadays many of the laboratories are equipped with complicated developing machines, that combine all the processes of developing, washing, “fixing,” and drying in one. Where prints, made from the original negative, are being developed, tinting is added. The undeveloped film, tightly wound in small rolls, is threaded through one end of the developing machine in the dark-room; it travels over little cog-wheels that mesh into the holes at the edges of the film, and goes down into a long upright tube filled with developer. Coming back out of this, still on the cogs, it travels next down into a tube of clear water for washing. Then down into another tube containing “hypo,” and up again for another tube and second washing. Then, still winding along on the little cogs it travels through a partition and out into a light room, where it passes through an airshaft for drying, across an open space for inspection, and is finally wound into as tight a roll as it started from in its undeveloped state. In the printing-room, still in the dim red light, we see half a dozen printing-machines at work, with raw film and negative feeding together past the aperture where the single flash of white light makes the exposure that leaves the negative image upon the print. Next, in daylight once more, we see the great revolving racks of the drying-room used for film developed by the hand process—with hundreds of feet of the celluloid ribbon wrapped around and around great wooden drums. In the assembling-room we find girls at work winding up strips of film and cementing or patching the ends of the film together to make a continuous reel.