After the slaughtered animal has been cleaned, scraped, eviscerated, washed, and split down the middle, the carcass is usually allowed to hang for an hour or so in a large room open to the outside air, known as the “hanging floor.” This is done with a view to getting rid of a certain amount of the body heat before the carcass is run into the chill rooms, and effects a saving in refrigeration. The carcasses are next run into “coolers” or chill rooms, and subjected to refrigeration with a view to ridding them entirely of their body heat. The coolers are large rooms fitted with brine pipes and capable of accommodating several hundred carcasses. The temperature of the coolers when the carcasses are run in is about 32° F. When filled, the temperature of the cooler rises to about 45° F., owing to the heat given off from the carcasses. The temperature is then gradually reduced to 28 or 30° F. Hog carcasses are left in the coolers as a rule for forty-eight hours, at the end of which time they are stiff and firm, but not frozen. The temperature of the chill rooms is always carefully watched, thermometer readings being made every few hours and duly recorded. The temperature of the carcasses is always tested when they leave the chill room. In those plants provided with a hanging floor, a certain number of the carcasses are also tested before they are sent to the chill rooms in order to determine the amount of heat lost on the hanging floor. The carcasses are tested by means of an especially constructed thermometer, known as a “ham thermometer,” which has a pointed metal protector so that it can be thrust into the body of the ham. (See fig. 4.) The ham has been rightly selected as the proper portion of the carcass at which to take the temperature, as it constitutes the largest mass of muscular tissue in the carcass and holds the body heat longer than any other portion. In taking the temperature, the thermometer is thrust deep into the body of the ham so that the point of the thermometer rests alongside or a little behind the upper portion of the femur or middle bone, the latter being used as a guide in introducing the thermometer. A certain number of the carcasses from each cooler are tested in this way as a check on the refrigeration. The inside temperature of the hams when they leave the chill rooms should be about 34° F. The carcasses are next cut up and the hams trimmed for pickling. In some houses the hams are given an additional chilling of 48 hours after they are cut from the carcasses, but this is not done as a rule, nor does it seem to be necessary.