=Whey Cheese.=—In Switzerland the so-called _Zieger cheese_ is made from sour whey, the albumin being coagulated by heat and, with whatever butter-fat there may be left in the whey, skimmed off the top. In Norway _Myseost_ (“Ost” is Norwegian for cheese) is made by boiling down whey almost to dryness. If goat milk is available to mix in, it improves the cheese. The main substance is sugar of milk and the cheese has a sweet, syrupy flavor. MILK SUGAR The by-product, sugar of milk, is produced by acidifying the whey, heating to boiling and neutralizing with lime until the albumin is coagulated. It is then filtered out and the clarified liquid is concentrated in vacuum. From the thick syrup the sugar is allowed to crystallize out, leaving the salts or mineral matters (milk-ash) in the remaining liquid. The use of milk-sugar is limited to medicinal purposes and for modifying milk for infants. The production is therefore not very extensive. CASEIN In a number of creameries casein is produced from skim milk by precipitating it with an acid and drying and pulverizing the precipitate. Casein is widely used as a substitute for ivory, in billiard balls, buttons, etc. It is also used as glue, and as a binder in paints. MILK POWDER The production and use of dry milk has increased enormously during the last few years and the processes of manufacture have been improved well-nigh to perfection. There are several methods practiced, the most important being the following: The _Just-Hatmaker_, in which a large metal drum or cylinder revolves slowly in a tank of milk. The drum is heated by steam inside and, as it rolls out of the milk, the metal surface picks up a thin film of milk which quickly dries and is removed by a scraper. The _Eckenberg_ process employs vacuum evaporating pans, like those used for making condensed milk and maple syrup. The _Merrell-Soule_ Company’s method consists in driving a blast of hot air into a fine spray of milk, which at once reduces the milk to a fine powder. In the “_Economic_” process the milk is dried by hot air the same as in the Merrell-Soule method, but in dropping through a tower from a height of some 30 feet the milk meets several blasts of air of different temperatures. It is claimed that in this way alone rich milk and cream may be reduced to a powder without injury to, or change of, the original fat globules. =Skim Milk Powder.=—Beautiful skim milk powders are now made which dissolve perfectly in water. Containing, as they do, the extremely nourishing constituents of the fatless milk in a most palatable form, they can be used in baking and in many food products to great advantage.