Singapore is the great emporium for gambier, and exported 34,248 tons in 1871, 19,550 tons having been imported, chiefly from Rhio and the Malay Peninsula. In 1876, the export increased to over 50,000 tons of pressed block, and 2700 tons of cubes. In 1877, it fell to 39,117 tons, owing to differences with the Chinese dealers concerning adulteration; of this quantity, 21,607 tons were for London, 7572 for Liverpool, and 2345 for Marseilles. The United Kingdom imports in 1872 were 21,155 tons, 451,737_l._, almost all from the Straits Settlements; in 1880, they were 26,061 tons, 461,781_l._, from the Straits, and 352 tons, 6468_l._, from other countries; total, 26,413 tons, 468,249_l._ Our re-exports in 1880 were:--2487 tons, 48,507_l._, to Holland; 1591 tons, 31,542_l._ to Germany; 1137 tons, 23,694_l._, to Russia; 594 tons, 12,026_l._, to other countries; total, 5809 tons, 115,769_l._ The approximate London market values are 15_s._ 6_d._-21_s._ 6_d._ a cwt. for block, 18-24_s._ for pressed cubes, and 23-27_s._ for free cubes. =Hemlock.=--The bark of the hemlock or hemlock spruce (_Abies canadensis_), of Canada and the United States, contains nearly 14 per cent. of tannin. The stripping of the bark commences in the southern parts of the United States in spring, and lasts during April-May; in New York, Michigan, and Wisconsin, the season is June-July; and farther north, it is still later. It is said that the best product is obtained farthest south. The destruction of the hemlock forests is fast approaching. Within the last 25 years, the preparation of an extract from the bark, containing 18-25 per cent. of a deep-red tannin, giving considerable weight and firmness to leather, has superseded the export of crude bark. One mode of preparing the extract is as follows:--The bark in pieces 1/2-1 in. thick, and several inches long, is soaked for about 15 minutes in water at 200° F. (93° C.); it is then fed into a hopper, which conducts it to a 3-roller machine, something like a sugar-cane mill, through which it passes, coming out lacerated and compressed; it next falls into a vat of hot water, where it is agitated by a wheel, that the tannin from the crushed cells may be dissolved in the water; hence it is raised by a series of buckets on an endless chain, somewhat in the manner of a grain-elevator, to another hopper, whence it is fed to another 3-roller mill; here it receives its final compression, and comes out in flakes or sheets, like coarse paper, and almost free from tannin. The buckets are made of coarse wire, that the water may drip through during the elevation. In order to avoid the blackening action of iron, wherever this metal will come into contact with the solutions it is thickly coated with zinc. The solution is evaporated to a solid consistency, generally by vacuum-pans. About 2 tons of bark are represented by 1 bar. (of less than 500 lb.) of extract. The chief makers are A. S. Thomas, Elmira, N.Y.; S. Brown &