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volcanic activity, and along the coast are earthy cones covered with green-sward, from which issue springs of muddy water emitting bubbles of gas. Copper, iron, and silver ore have been discovered ; but the island is chiefly noted for its petroleum wells, the oil derived from which is of excellent quality, and is extensively used in the com position of paint, as it preserves wood from the ravages of insects. Timber is not abundant, but the gamboge tree and the wood- oil tree are found of a good size. Tobacco, cotton, sugar-cane, hemp, and indigo are grown, and the staple article is rice, which is of superior quality, and the chief article of export. The inhabitants of the island are mainly Mughs. Cheduba fell to the Burmese in the latter part of the last century. From them it was captured in 1824 by the British, whose possession of it was confirmed

in 1826 by the treaty concluded with the Burmese at Yandaboo.

CHE-FOO, or Yen-tai, as it is called by the natives, a seaport town of Northern China, on the southern coast of the Gulf of Pih-chih-li, in the province of Shan-tung near the mouth of the Yi-ho, and about 30 miles east of the city of Tang-chow-foo. Till recently it was quite a small place, and had only the rank of an unwalled village; but it was chosen as the port of Tang-chow opened to foreign trade in 1858 by the treaty of Tien-tsin, and it is now the residence of a Tau-tai, or intendant of a circuit, the centre of a gradually-increasing commerce, and the seat of a British consulate, a Chinese custom-house, and a considerable foreign settlement. The native town is yearly extending, and though most of the inhabitants are small shop-keepers and coolies of the lowest class, the houses are for the most part well and solidly built of stone. The foreign settlement occupies a position between the native town and the sea, which neither affords a convenient access for shipping nor allows space for any great extension of area. Its growth, however, has hitherto been steady and rapid. Various streets have been laid out, a large hotel erected for the reception of the visitors who resort to the place as a sanitarium in summer, and the religious wants of the community supplied by a Roman Catholic and a Protestant church. Though the harbour is deep and extensive, and possessed of excellent anchorage, large vessels have to be moored at a considerable distance from the shore. The foreign trade is mainly in the hands of the English and Americans, the Germans and the Siamese ranking next in importance. In 1872 there entered the port 233 British vessels, with a tonnage of 97,239 tons and cargoes valued at £144,887; while in the same year the ships of all other nationalities numbered 348, with a tonnage of 149,197 tons and a value of £177,168. The imports are mainly woollen and cotton goods, iron, and opium; and the exports include bean-cake, bean-oil, and peas, raw silk, and straw-braid manufactured by the peasants of Lai-chow-foo, walnuts from Tsing-chow-foo, a coarse kind of vermicelli, vegetables, and dried fruit. A certain amount of trade is carried on with the Russian settlements of Manchuria, in which the edible sea-weed gathered in the shallows of the coast are exchanged for piece goods, liqueurs, and sundries from China.

CHEESE, a solidified preparation from milk, the essential constituent of which is the proteinous or nitrogenous substance casein. All cheese contains in addition some proportion of fatty matter or butter, and in the more valuable varieties, the butter present is often greater in amount than the casein. Cheese being thus a compound substance of no definite chemical composition is found in commerce of many different varieties and qualities ; and such qualities are generally recognized by the names of the localities in which they are manufactured. The principal distinctions arise from differences in the composition and condition of the milk operated upon, from variations in the method of preparation and curing, and from the use of the milk of other animals besides the cow, as, for example, the goat and the ewe, from the milk of both of which cheese is manufactured on a commercial scale.

The quality and the composition of the milk operated on are of prime importance in cheese-making. Not only does this substance vary widely in richness and flavour owing to the breed, the nature of the food, and the state of the health of the animal yielding it, and many other circumstances ; but in cheese-making the differences are still further increased, in some cases by adding cream to it, and in others by using it as skim-milk or milk deprived of a portion of its fat. Taking as a standard the ordinary sweet milk of cows, the following analyses (No. 1 given on the authority of Dr Parkes, and No. 2 by Dr Voelcker) may be taken to represent its average composition:—

Composition Water Butter Casein Milk Sugar Mineral matter . No. 1. 867 3-7 4-0 5-0 6 No 2. 86-65 3-99 3-47 5-11 78

The object of the cheese-maker is to obtain in a solid form as large a proportion as possible of the casein and butter contained in the milk dealt with. The poverty in these constituents of the whey or liquid matter separated in the process of making cheese is therefore, to some extent. a measure of the success of the operation. The average composition of the whey drained off may be thus stated:—

Water 92"95 Butter -24 Casein 81 Milk Sugar and Lactic Acid 5 27 Mineral matter -"3

Milk, as is well known, if allowed to stand for some time, becomes thick, and is then separable into two portions a solid white curd, and a greenish liquid whey. Such a coagulation and separation is essential in the making of cheese ; but only to a small extent, in Holland and some other localities, is the natural acid coagulation taken advantage of. It has been assumed that the solid con stituents of milk are held in solution by an alkaline substance, and that coagulation is the result of the neutra lization of the alkali by the development within the fluid of lactic acid, as in the case of sour milk, or by the addition of an acid substance as is sometimes the practice ; but this theory does not satisfactorily account for all the phenomena of coagulation. Acid substances, however, do readily curdle cheese, and hydrochloric acid, tartaric acid, vinegar, and cream of tartar have all been employed to produce coagula tion for cheese-making. The curding is also, in practice, produced by the action of such substances as the juice of figs, and decoctions of thistle tops, artichoke flowers, the butter-wort, and other plants, But the substance used uniformly in Great Britain, and in all great cheese-producing districts, is rennet, a preparation of the fourth or digesting stomach of the suckling calf. Rennet is prepared by cutting up the membrane in strips, salting, smoking, and sometimes treating it with spices and aromatics. The influence of rennet is due to the fact of its exciting a kind of fermentative action; but that it thereby changes the sugar of milk (lactin) into lactic acid, and so coagulates the casein, has been denied by Dr Voelcker, who holds its action to be " sui generis, and as yet only known by its effects."

In the practice of cheese-making it is found necessary,

in order to hasten the coagulating action of rennet, and to produce a curd of sufficient hardness, to heat the milk to a temperature which varies from 72 to 85 or 90 Fahr. The

lower temperature, it is found, yields a soft cheese, retaining