The hard cheeses form a great series of groups, whose most prominent physical character is their firm or hard texture. This is correlated with comparatively low water-content, which is usually between 30 and 40 per cent. Although certain varieties occasionally test above 40 per cent water, this deviation is accompanied by quick ripening and rapid spoilage. These varieties of cheese are staple products with long marketable periods; therefore they may be handled in large lots, shipped, carted and stored freely without the losses such treatment would entail in soft cheese. The retailer frequently buys hard cheese by the ton, not by the cheese or by the box. In making, these varieties are characterized as cooked and pressed cheeses. Although both the heating of a curd and the pressing of a newly made cheese occur among semi-hard forms, these practices appear in their most typical forms in the hard cheeses. The hard cheeses show two types of texture. A cut cheese may appear smooth, free from holes or with a few angular cracks or seams, or it may show round holes or "eyes." In the smooth textured forms every effort is made to prevent gassy fermentations, usually by controlling the fermentation of the curd in the making process. When "eyes" are present, the end sought has been a development of a particular form of gassy fermentation which gives this appearance and brings about the characteristic ripening texture and flavor. The hard cheeses have been developed in groups of national varieties. The best known of these groups are those which may be represented by English Cheddar, American Factory Cheddar, Danish, the Edam of Holland, Swiss and Parmesan with many related varieties in Italy and neighboring countries of southern Europe. +181. The Danish group.+--The Danish cheeses are related in appearance and flavor to the English group represented by Cheddar. The demand for butter in Europe has been so great that the Danish cheese-makers have developed skim and part skim varieties largely to the exclusion of the whole milk form. Skillful handling of their process has resulted in a product which has had a very large and appreciative market in England and Germany. +182. The Dutch group.+--Edam and Gouda are the two forms of cheese made in Holland and most widely known among other peoples. Both reach America in considerable quantities; both are shipped in large amounts to tropical countries. Although attempts have been made to manufacture them in America, no commercial production of these cheeses has been successful. Although whole milk grades of these cheeses are known, they are to a large measure part skim in manufacture. The presence of one or both of these forms in every large market in America makes the general facts of their production of general interest. Parts of a report on experimental work in the making of Edam and Gouda are, therefore, given here.