mill. The mill consists of a roller provided with very coarse teeth,

which revolve through similar stationary teeth; the material is retained by a semi-circular perforated plate until it is reduced to the size of the perforation, or about the size of a coffee bean, when it is then ready for the burr stones.

In ground ginger little of its structure is seen beyond the starchy grains which can readily be distinguished by their shape and by their fibrous, vascular bundles which are easily traceable. In the unscraped ginger the outer horny layer is to be seen, but not distinct in its character at any time, and when scalding of the rhizomes takes place, the starch grains are swollen and it is more difficult to find the foreign particles. Good powdered ginger should have the fibers taken out by sifting.

The best ginger cuts pale, but bright, with a varied color, both outside and inside. Its consistency is ascertained by cutting, and varies from hard to soft or, as is termed in the trade, flinty, the soft being the best. The popular medicinal stimulant known as Jamaica ginger extract is an alcoholic extract of ginger root, and is often resorted to by old topers who can no longer be satisfied with whiskey.

Salable essence of ginger is made by taking one pint of strong tincture of the finest Jamaica, to which add in small portions at a time finely powdered slacked lime, shaking vigorously after each addition, until the tincture ceases to lose color, then throw the whole upon a filter and pass through the residue proof spirit until the product will measure two pints. Next add, drop by drop, diluted sulphuric acid until the rich yellow of the tincture suddenly disappears. Let it stand twenty-four hours, dilute with water to four pints, and shake with a little powdered pumice or silica and filter at 0 degrees C., if possible.

Ginger lozenges are used as a confectionery which frequently benefits dyspepsia and generally encourages flesh.

Ginger-beer powders are made by mixing two ounces of white sugar with twenty-six grains of bicarbonate of soda, five grains of powdered ginger, and one drop of essence of lemon, put in white paper. In blue paper put half ounce of tartaric acid. In drinking use in the same way as seidlitz powder.

The following is a good recipe for making ginger beer, and it has a high medical authority as yielding a very superior beverage, and one that will keep for several months: White sugar, twenty pounds; lemon juice, eighteen fluid ounces; honey, one pound; bruised ginger, twenty-two ounces; water, eighteen gallons. Boil the ginger in three gallons of water for half an hour, then add the sugar, the lemon juice, and the honey with the remainder of the water, and strain through a cloth; when cold, add the white of one egg and half an ounce of essence of lemon; after standing for four or five days, bottle. The bottles should be laid on their sides in a cellar, and the beer is ready for use in about three weeks. If a little yeast has been used the beer is ready in about two days, but in this case the beer does not keep well.

The principal consumption of ginger is not only as a useful aromatic spice, but when applied to the nostrils it acts as an irritant and produces sneezing. The native doctors prize it highly as a stimulant. It is especially valued for paralytic and rheumatic troubles, and also for intermittent fevers. Europeans often use infusions of ginger for delicate nerves in place of tea. The green root cut into strips and steeped is thought to be superior to the dried root.

Rhizome chewed relieves toothache and powerfully increases the flow of saliva, and to the stomach it operates as a stimulant, first to the alimentary canal and, secondly, to the body in general, especially the organs of respiration. In enfeebled and relaxed habits, especially of old and gouty individuals, it promotes digestion and relieves flatulency and spasms of the stomach and bowels. It checks and prevents nausea and griping, which is sometimes produced by some drastic purgative, and a ginger plaster when applied to the forehead will relieve headache. When powdered and used with hot water and applied externally it produces a sensation of intense heat, and slight redness, and adds cordial qualities to the tonic.

Powdered ginger may be taken in doses of ten grains or more in the form of a pill or in tea. When used to excess, however, it is very dangerous, as it slowly destroys the lining of the stomach and causes lingering pain and agonizing death.

Ginger contains a great deal of alcohol. This fact accounts for the formation of the so-called ginger habit to which the victim becomes a slave as to the whiskey, opium, or tobacco habit. Indulgence in this habit is more dangerous because ginger is supposed to be harmless.

A careful qualitative examination of the character of the extracts at times may reveal the presence of an adulterant, but the chief dependence is examination under the microscope. The microscope, however, will not reveal the presence of exhausted ginger, and a careful study of the effect of exhaustion on the proximate composition of the ground root is, therefore, desirable. It would naturally increase the relative percentage of fiber and albuminoids and starch, and diminish that of the extract matter.

There is a variety of ginger known and cultivated by the Chinese under the name of _Galangal A. officinarom_. It is very thick and slightly flattened and is prized by the Siamese and Chinese as a substitute for ginger. In Siam it is known as Alpinia. There is also a variety found and cultivated in Siam similar to Alpinia allughas, called luk reu or bastard cardamom, which has the cardamom-like fruit. Ginger usually comes to New York in 110 to 120-pound bags and 130-pound barrels.

The yield of oil from ginger is from 1.9 to 2.7 per cent., having a specific gravity at 15 degrees C. of 0.880 to 0.885, and an optical rotation of 25 to 40 degrees in a 100-millimeter tube.

The chemical composition of ginger oil remains unknown, but it is known to contain camphene and other ingredients; its complex nature is indicated by the wide range of its boiling point.

When distilled, after drying over CaCl_{2}, the boil begins to pass over at 140 degrees C., accompanied by a few drops of aqueous fluid, the temperature constantly and rapidly rising to about 240 degrees, the chief portion of the oil coming over between 240 degrees and 270 degrees C. and a little passes over between 270 degrees and 300 degrees, but evidently accompanied by decomposition products, a transparent, brown, tenacious, semi-solid residue remaining in flask.

The lower boiling products retain the ginger aroma, which is noted when diluted with spirits, and are much more soluble in rectified spirits than higher fractions. Oil of ginger is yellow in color and its odor is intensely like that of the root; that of Jamaica is the most fragrant, but has not the burning, pungent taste of ginger, which is due to gingerol, the active pungent principle of the root.

Gingerol exists in the dried rhizomes to the extent of from 0.600 to 1.450 per cent. It is of a pale straw color and odorless, with a pungent, bitter taste. It is soluble in alcohol in even 50 per cent. dilution; it is also soluble in benzene, volatile oils, carbon disulphide, solution of potash and ammonia, and glacial acetic acid, and very slightly soluble in petroleum ether, consisting of resin, starch, mucilage, and paraffine, organic acids, oxalic acids as CaC_{2}C_{4} cellulose albuminoids, etc., which constituents of ginger are found to be odorless and tasteless.

The alcoholic solution is neutral in reaction and gives no precipitate with the acetates of lead nor with lime, and does not yield glucose when treated with diluted sulphuric acid. Strong sulphuric acid dissolves it with the production of a brown color; hydrochloric acid does not affect it. Nitric acid converts it into a blood-red resinous substance.

Adulterants of ginger are sago, tapioca, flour of rice, wheat, and potatoes, Cayenne and mustard hulls, and tumeric and exhausted ginger. The foreign starches, Cayenne, and mustard hulls are easily detected, but the tumeric (East India arrowroot) cells, from their resemblance to the resin globules of the ginger, are most confusing. For detection of exhausted ginger recourse must be had to proximate analysis.

Chemical composition of ginger:

Ash may vary from 3.4 to 8 per cent.; fiber, 1.7 to 9 per cent.

The white ginger has less ash than the dark, as is also the case in regard to the percentage of fiber.

Water, 11.00 to 9.10 Ash, 7.02 to 3.39 Volatile Oil, 2.54 to .96 Fixed Oil, 4.58 to 2.29 Starch, 53.33 to 46.16 Crude Fiber, 7.65 to 1.70 Albuminoids, 10.85 to 5.25

It is said that the water and starch extract from the weight of the newly dug root 75 to 85 per cent., and yet the dried root retains all the valuable aromatic qualities.