In 1846, 563 tons of bark for tanning were exported from Port Phillip.

A large quantity of tannin is extracted from various species of Eucalyptus, the gigantic gum trees in Australia and Van Diemen’s Land (of which quarter all the species are natives), and sent to the English market; it is said to be twice as powerful in its operations as oak bark.  Some of these trees attain a height of 200 feet.  Their bark separates remarkably into layers.  A sort of kino gum, an astringent resinous-like substance, is also extracted from E. resinifera, the brown gum-tree of New Holland, which is sold in the medicine bazaars of India.  It exudes in the form of red juice from incisions in the bark.  A single tree will often yield 60 gallons.  In Brazil they use the bark of Luhea panicata, an evergreen climber, for tanning leather; and in Peru the bark of some species of Weinmaunia serve the same purpose.  Among other powerful astringents I may notice the root of a species of Sea Lavender (Statice Caroliniana), Myrica cerifera, and Heuchera Americana, all natives of North America.  Also the petals of Hibiscus Rosa-sinensis, a native of Asia.

The sea-side grape (Coccolaba uvifera) yields an astringent substance, known as Jamaica kino.

The bark of the Cassia auriculata, and the milky juice of the Asclepias gigantea, are used for tanning in India.

The red astringent gum obtained from Butea frondosa, a middling size tree, common in Bengal and the mountainous parts of India, is used by the natives for tanning.  English tanners, however, object to its use on account of the color which it communicates to the leather.

The barks of the Mora excelsa, Benth; Courida (Avicenna nutida), cashew (Anicardium occidentale), guava and hog-plum (Spondius lutea, Linn.), have all been successfully used for tanning in Demerara and the West India Islands, where they are very abundant.  Specimens were sent from British Guiana.

The root of the Palmetto palm (Chaemaerops Palmetto) is stated to be valuable for the purposes of tanning.  The leaves of Nerium Oleander contain tannic acid.  The bark of a species of Malphigia is much used by the Brazilians.

The panke (Gunnera scabra) is a fine plant, growing in Chili, on the sandstone cliffs, which somewhat resembles the rhubarb on a gigantic scale.  The inhabitants eat the stalks, which are subacid, tan leather with the roots, and also prepare a black dye from them.  The leaf is nearly circular, but deeply indented on its margin.  Mr. Darwin measured one which was nearly eight feet in diameter, and therefore no less than twenty-four in circumference.  The stalk is rather more than a yard high, and each plant sends out four or five of these enormous leaves, presenting together a very noble appearance.

The barks replete with the tanning principle should be stripped with hatchets and bills from the trunk and branches of trees in spring, when their sap flows most freely.  The average quantity of oak bark obtained from our forests is estimated at 150,000 tons annually, of which Ireland and Scotland furnish but a very small quantity.