Butter, Potting.--The best month of the year in which to pot butter is May, or, at any rate, the business should be completed before the hot weather comes on. If the butter is to be kept for several months, it will be necessary to put a good deal of salt with it; 1 oz. salt to 1 lb. butter will not be found too much. To ensure the proper incorporation of the salt, it is best to add it by small quantities at a time, kneading and re-kneading the butter till the whole is thoroughly mixed. It must then be pressed firmly into wooden tubs, or “kits,” as they are technically called; or stone jars may be used if preferred. It is hardly necessary to add that great care must be taken to have every vessel employed in the preparation as clean and sweet as possible. Another very simple way to preserve butter is to have a good-sized earthenware jar or pan filled with some strong brine, and place it at hand in the dairy. Into the brine put from time to time, as it can be spared, ½ lb. of fresh butter, each piece being folded up separately in thin muslin. The only care required is to be certain that the butter is always thoroughly covered with brine: it will sometimes be necessary to put a weight on the butter, as it has a tendency to rise to the surface when the brine is strong. The butter will keep in this manner for weeks, or even months, and, besides the advantage gained by this plan of being able to take out just as much as is required for use at a time; there is the additional benefit of having preserved fresh butter, as it does not absorb the salt. Butter, Rancid.--(_a_) Rancid butter may be recovered and sweetened by washing and kneading it well, first in new milk, and afterwards in cold spring water, butyric acid, on which the rancidity depends, being freely soluble in new milk. (_b_) Let the butter be melted and skimmed as for clarifying; then put into it a piece of bread, well toasted all over. In a minute or two the butter will lose its offensive smell and taste. (_c_) Beat the butter in a sufficient quantity of water, in which you put 25-30 drops lime chloride to 2 lb. butter. After having mixed it till all its parts are in contact with the water, it may be left in for 1-2 hours, afterwards withdrawn, and washed anew repeatedly in fresh water.