and facility of securing any temperature is very desirable, as a matter of convenience, wherever the operations are conducted on a large scale. But the same result could be easily obtained on a more limited scale in photographic dishes, and having at hand a large vessel of hot water, as well as the ordinary cold water supply.
Where hot and cold water are not convenient, the following arrangement will be found very useful:
A wooden frame-work is made of the desired height, similar to a table with an open top, and a cross-piece in the centre. A and B are metal pans four to six inches deep, placed in the open top, suspended there by their rims, and heated by a gas-burner or the stove C. One of these is used for cold or tepid, and the other for hot water. It is convenient to have a thermometer in each pan.
The prints are first immersed in cold water, all air-bubbles being carefully removed. Here they are left for half an hour or more, as may be convenient, to permit the water to penetrate and soften the gelatine; after
