Milk, cheese, and butter : a practical handbook on their properties and the processes of their production, including a chapter on cream and the methods of its separation from milk / by John Oliver.

  • Oliver, John (Writer on dairy products)
Date:
1894
Catalogue details

Licence: Public Domain Mark

Credit: Milk, cheese, and butter : a practical handbook on their properties and the processes of their production, including a chapter on cream and the methods of its separation from milk / by John Oliver. Source: Wellcome Collection.

Provider: This material has been provided by The University of Leeds Library. The original may be consulted at The University of Leeds Library.

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    Oxides—NaoO, KoO, CaO, MgO, FeO, FcoO.,, &c. Alkaline hydrates—KOH, NaOFI. Ammonia—N H3. Acids —HoCO;,, HNOy, H2SO4, H;,POj, forming, with the alkaline bases, carbonates, nitrates, sulphates, and phosphates. Silicates—Soluble, formed by combination of SiOo with alkalies. Chlorides—CaCL, KCl, MgCl.,. These are either combined with each other or uncombined, accord- ing to circumstances ; and being very variable in their proportions, there are always present uncombined remainders of some of them. They are not all present at all times. Thus a limestone will contain some of them, a sandstone others, with some common to both, and even the composition of rocks of the same class will differ. The mineral constituents of soils depend, therefore, upon their original sources, and the physical and chemical changes wrought in them by the forces of nature. Organic Substances.—These are found in soils as the products of the decay of organised animal and vegetable bodies, especially of the latter. Everybody knows how wood rots away into the mould so valued by the gardener. The same process is continually going on with the dead leaves and roots of plants, and the general product is called humus. This contains several acids of the Carbon- acid type, consisting of C, H, and O in varying proportions, and which—because of their origin—are called organic acids. Of these, hicmic acid, C.joHioOr, is an e.xample. Besides the services rendered by these acids, humus takes up the valuable ammonia, NH3, formed in or furnished to the soil, and holds it well for use by plants. Nor must we forget the soluble earthy matter brought to the soil in the farmer’s manures, for these become a part of the soil for all practical purposes. Here are many forms of matter, organic and inorganic, undergoing decomposition in the chemical sense, and being thereby prepared for new uses. Plant Life. — Now comes the seed, which finds shelter and anchorage under the suiface, moisture, and the warmth absorbed from the sun’s rays ; and with these conditions its life-germ becomes active, throws out roots, stem, and leaves, and becomes a plant. At first, feeding upon the stores of food within itselfj it is ready, when they are exhausted, to take them up from the soil. Then the stores of soluble organic and inorganic materials already described are drawn upon for whatever the plant needs. Different plants re- quire different foods, or different proportions of the same food, in order to their best growth and increase ; and they will be vigorous or weak, luxuriant or puny, according to the sufficiency or deficiency