Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/169

157 HOP 157 produces a larger quantity than any other country in Europe. Formerly several plants were used as well as hops to season ale, hence the name &quot; alehoof &quot; for Nepeta Glechoma, and &quot; alecost &quot; for Balsamita vulgaris. The sweet gale, Myrica Gale, and the sage, tialvia officinalis, were also similarly em ployed. Various hop substitutes, in the form of powder, have been offered in commerce of late years, most of which appear to have quassia as a chief ingredient. The young tender tops of the hop are in Belgium cut off in spring and eaten like asparagus, and are forced from December to February. They are not only considered a delicacy, but valuable as a diet for anoemic, scrofulous, and rachitic persons. FIG. 2. Fruit of Hop. Hops are extensively cultivated in parts of New England, New York, and Michigan, and most of the hops consumed in the United States are supplied by those districts. Al though the hop was introduced into America nearly 250 years ago, and its cultivation encouraged by legislative enactments in 1657, it is only about seventy-five years since its culture was commenced on an extensive scale ; but from that time the progress has been rapid, and hops have been grown in nearly every State in the Union. The amount produced in the United States was estimated in 1840 at 6196 bales, in 1850 at 17,485, in I860 at 54,900, and in 1870 at 127,283. As in England, the hop is subject to disease and blight, and in consequence the crop is variable ; thus, in 18G9, 69,463 bales were exported from New York and none imported, and in 1873 only 315 bales were exported and 20,885 imported. The English cluster and grape hops seem to be most generally cultivated in New York and Wisconsin. Hops are also grown largely in Bel gium, Prussia, France, Wiirtemberg, and central Germany. In 1879 only 7153 cwts. of hops were exported from England chiefly to Australia and other British possessions, while 262,765 cwts. were imported, of which 108,306 cwts. were derived from the United States, 63,485 cwts. from Belgium, 50,567 from Germany, 26,796 from Hol land, and smaller quantities from France and British North America. The first packages of hops collected in England often fetch an extravagant price, and are some times disposed of with remarkable celerity. The first pocket of hops gathered in 1879 is said to have been picked, dried, sent to London, sold by auction, subjected to hydraulic pressure, packed and banded with iron, covered with three coats of paint, and despatched to an Indian mail steamer all within twenty-four hours. The better qualities are usually packed in fine and the inferior in coarse sacking. In Germany two varieties of the hop are distinguished, the August and the autumn hop, the former being preferred. The stem of the hop abounds in fibre similar to that of hemp and flax, and has been used in Sweden in the pro duction of a strong durable white cloth. Hitherto it has been usual to steep the stem in water during the whole winter in order to separate the fibre easily. A much quicker process has, however, been patented, by which the fibre can be speedily extracted. This process consists in boiling the stems first for three quarters of an hour in alkaline lye, and then, after rinsing in water, for the same time in acetic acid ; the fibre is thus obtained in a state fit for bleaching. The leaves, stem, and root possess also an astringent property, and their use for tanning purposes was hence at one time patented in England. The leaves have also been recommended as fodder in the fresh state, mixed with other materials, and are said to increase the quantity and improve the quality of milk yielded by cows. The stems or &quot; bine &quot; are usually burned in the hop garden. The spent hops from breweries form excellent manure for light soils, and together with the leaves should be re turned to the hop-gardens, the materials absorbed from the ground by the hop plant being thus in some measure restored to it. By distillation with water, hops yield - 9 per cent, of a volatile oil, of a greenish colour if from fresh, but reddish- brown if from old hops. Exposed to the air it resinifies. This oil, according to Personne, contains valerol, C H 10 O, which soon passes into valerianic acid, O l to 17 of this acid having been found by Mehu in the lupulinic glands. The unpleasant odour of old hops is due to this change, which may be prevented or retarded by exposure to the action of sulphurous acid gas. For medicinal use fresh hops which have neither undergone this change nor been treated with sulphurous acid should be used. For brewing purposes, according to Liebig, the use of sulphured hops is not objectionable. The bitter acid principle, C 3 oH 5u O 7, to which hops probably owe their tonic properties, although noticed by Payen, was first obtained in the pure state by Lermer in 1863. It crystallizes in large rhombic prisms, and is soluble in ether. It has been variously called lupulin, lupuline, lupulite, and humulin. Griessmayer (1874) has shown that hops contain also in small proportion a liquid volatile alkaloid, not yet analysed, which has the odour of conia ; to this alkaloid its narcotic property is perhaps due. The same chemist found trimethylamine in hops. Etti (1876-78) has found in the scales of the hop strobiles an astringent principle, hiimulotannic acid, Cr )0 H 48 2r), which is incapable of precipitating gelatin, but which, when boiled in alcohol or water or heated to 130 C., changes to a red substance, p/tlobaphen, C 50 H 40 O 25, whose solution in alcohol possesses that property. Etti likewise obtained a crys talline white and an amorphous brown resin, 1 also malate, 1 Issleib (Archiv der Pharmacie, May 1880) has further elucidated the chemical relationship of the constituents of the resin, essential oil, and bitter principle.