Salt and saltpetre are the active agents used for freezing. The quantity employed is one pound of salt for four pounds of ice, this being a proportionately active mixture for freezing the very richest cream and water ices. The salt and ice can be ranged in alternate layers or else have the whole mixed well together in a pail; in either case place ice around the freezer and pack it down well with the palette. Repeat this operation every time more salted ice is to be packed.

Always pay attention that sorbetieres turned by hand are to be packed lower than the edge of the pail, so that when the ice is finished the cover of the freezer may be adjusted as well as the cover on the pail. In houses where ices are being constantly made they have boxes lined with galvanized sheet-iron cylinders, and the empty space between the box and the cylinder is filled either with charcoal dust, tow or sawdust, as well as the covers; each cylinder must be provided with a hole one inch in diameter and two inches from the bottom to allow the water to run out. In case the water should not be allowed to flow off, then it will be prudent to bore a hole half an inch in diameter, one inch lower than the height of the freezer.