The commercial value to those engaged in creamery management of knowing the moisture content of butter has created a want for some simple and accurate means of ascertaining the percentage of water in butter. The recent stringent enforcement of the pure food law has emphasized its need in the case of dealers. To meet the demand several methods have been devised and placed upon the market. In the use of these, reliability of results has been questioned, and it has been felt that official tests should be made to determine their accuracy.

This bulletin gives a description, of the methods commonly used, with comments upon them. Their results are compared with the standard gravimetric analysis recognized by the Association of Official Agricultural Chemists. In making comments, the writers have taken into consideration conditions as they exist throughout the creameries. Simplicity of method, cost of apparatus, expense of manipulation and the intelligence of the labor employed, are also dealt with. Variations in the water content, so far as they affect the results of the methods, are given general consideration.