In Duclaux’s own district of Cantal, a soft, quickly maturing, uncooked cheese is made, which has the disadvantage of slowly depreciating after ripening, owing to the large quantity of moisture it contains. The practice is to curdle the milk rapidly, and then, while the curd still retains a considerable amount of whey, to allow it to ferment till all the milk sugar has disappeared. On pressing the mass, there is squeezed out a certain amount of liquid and much ferment; but the remainder, equivalent to half the weight of the cheese, is retained, owing to a curious change in the properties of the curd. So obstinately is this held, that, with additional pressure, fat is forced out in preference to water. Duclaux finds, however, that with cheese containing less fat--say, half skimmed and half raw milk--more liquid can be extracted, and thus a better-keeping cheese obtained. As the flavour and odour are derived almost entirely from the alteration products of the casein, the main characteristics of the Cantal cheese are not altered by this modification, and he consequently recommends its adoption. The most praiseworthy part of Duclaux’s investigations--that on the life history of these organisms, and the isolation and investigation of the diastases secreted by them--is of too scientific a nature to be reproduced here. We may mention, however, that Manelli and Mussi, in their researches on the maturing of Parmesan cheese, have independently come to much the same conclusion as those given above; so there is every reason to consider that we possess now a correct explanation of the phenomena of cheese ripening.