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 with a spray of cold water for several hours, and they are then dried, painted, and labeled.

The above is a general description of the process employed which, however, is varied to some extent in different packing houses.

A modification of the above method consists in exhausting the cans in vacuo and automatically sealing them in the exhausted state, thus removing all air and other gases therefrom. The cans are then placed upon an endless conveyor and dipped into an oil bath at a temperature of 240 degrees, the speed of the conveyer being so regulated that the cans remain in the bath a sufficient length of time to complete sterilization before being carried out at the opposite end. After passing through this bath they are carried automatically into another bath consisting of a solution of carbonate of soda and, finally, into a bath of pure water. The cans are then painted and labeled as originally described.

SPECIAL STUDIES OF METHODS OF CANNING BEEF MADE IN BUREAU OF CHEMISTRY.

Composition of Beef Used for Canning.—Samples of fresh beef intended for canning purposes, and examined in the Bureau of Chemistry, have the following composition:

Water,                                    71.17 percent Insoluble protein,                        13.87    " Globulins,                                  1.38    " Proteoses, peptones, and gelatin,          1.31    " Meat bases,                                 1.09    " Fat,                                       9.89    " Ash,                                         .96    " Salt,                                       .04    " Undetermined,                                .33    "

The sample, of which the above data are representative, was secured from a mass of meat weighing 356 pounds, after passing through a sausage grinder and being thoroughly mixed. The above data may therefore be regarded as the representative constituents of the usual grade, most carefully selected canning beef.

Effect of Parboiling.—A similar lot of meat secured in the same way and from the same carcass weighed 358 pounds and was parboiled as follows: The meat was placed in water in a steam-jacketed tank, the temperature of which stood at 196 degrees F. The reduction in the temperature caused by the meat was restored by heating the contents of the retort, and it was kept at 196 degrees F. for 15 minutes. It is thus seen that this parboiling was accomplished at a temperature below the boiling point of water. After the parboiling was completed it was found that the meat weighed 235 pounds, showing a net shrinkage in weight of 123 pounds. This sample of meat was