The inspissated juice of an Indian plant, which grows also in Malacca, and is largely used in dyeing and tanning. It is principally imported from Singapore.

The composition of coal gas as produced for illuminating purposes depends very largely upon the temperature at which the roasting of the coal takes place, and upon the amount of air that gains access to the retorts. It contains not only permanent gases but, in addition, considerable quantities of the vapours of volatile hydrocarbons, to which its luminosity in burring is due. The greater proportion consists of hydrogen, which burns with a practically colourless flame, and marsh gas or methane , which also gives but little light when burned alone. Accompanying these constituents there are proportions of carbon dioxide, carbon monoxide, nitrogen, and oxygen. The illuminating power of coal gas is chiefly attributable to olefiant gas and other associated hydrocarbons, which, in all, amount to about 5 per cent., and the process of roasting the coal is conducted in such a way as to yield about 10,000 cubic feet of gas per ton of coal. In 1913, about twenty million tons of coal were carbonized in the United Kingdom for the manufacture of coal gas. The composition of good coal gas according to one analysis, which is fairly representative, is as follows: The gas, however, now supplied in many places consists of a mixture of ordinary coal gas with socalled water gas, or carburetted water gasthat is, the mixture of carbon monoxide and hydrogen which is produced by passing steam over redhot coke, while at the same time a certain quantity of petroleum is introduced and destructively decomposed or “cracked” in the furnace, to give to the other gases that proportion of hydrocarbons necessary to givelmnin osity to the whole mixture when it is burned.

See Dextrose, Glucose, Sugars, and Carbohydrates.

A thick, viscid oil, apt to become crystalline, distilled from the wood of some species of guaiacum, known as “balsam wood” in South America. * t is soluble in alcohol and ether, has a sp. gr. of about oyfi to og8, with optical rotation 6 degrees to and is used in perfumery.

The mineral matter enclosing or intimately associated with metallic and other ores.

A white, crystalline substance, which melts at about 2340 C., soluble in water and of sweet taste, which behaves both like a base and an acid forming saltsthat is to say, with both acids and bases. It can be prepared chemically by several methods, but it is especially interesting considered as a derivative of wool and silk and as a product of the hydrolysis of certain albuminous bodies, because it is believed that a mixture of aminoacids, together with sufficient amounts of fat, starch, sugar, and the necessary saline bodies, will maintain life without the use of proteins.

A class of proteins insoluble in water but soluble in a dilute solution of salt, including globulin from the crystalline lens of the eye, and fibrin of blood.

There are many forms of laboratory gas generators, bottles and flasks properly fitted up being often employed, and particularly the latter when it is necessary to employ the agency of heat. Kipp

is used in flavouring and in compounding liqueurs.

is the dried root of the Gtntiana lutea which grows abundantly in Switzerland, the Tyrol, and the Auvergne. An aqueous infusion is used as a bitter tonic in medicine, a substance named gentianic acul being considered the chief active principle. The root contains a yellow colouring matter.