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when not in use, may be preserved from dry-rot by hauling them out of the water in an exposed situation where the wind will get to them, keeping sky-lights and hatches open, and if a plank be removed from the bottom they are all the safer. Should they be entirely closed up, on the other hand, the dry-rot will flourish within like mushrooms in a hot-bed. Sap-wood should always be removed from the timbers and planks of a ship, as, from its spongy texture and imperfect development, it is more liable to dry-rot than the heart-wood (besides being much weaker;) and when the dry-rot has once commenced, either in a ship or a house, it is rapidly propagated by contagion. The process of seasoning timber quickly by a current of heated air will be found amply detailed in the article Ship-Building. Timber is bought and sold by solid measure, according to the number of cubic feet in the tree or log. The measurement of timber is therefore the operation by which these cubic contents are determined; that is, multiplying together the three dimensions, the mean length, the breadth and the depth of each log. If the log should vary much in size in different parts, then the length, breadth and depth of each of these parts must be multiplied together, and the contents of the log will be the sum of the products. When the log tapers, a mean breadth or depth is taken; the object in every case being, to attain the most correct approximation to the contents of the log. In measuring rough logs it is, however, usual to gird the log at the measuring place with a string, and then, folding the string into four equal parts, to assume this fourth part of the girth to be one side of the square area at the measuring place; which area, when multiplied by the length, will give the solid contents of the log. The arithmetical operation, simple as it is, is universally superseded by the more simple and far more correct plan of referring to published tables of contents, calculated for every foot in length of a log, and every quarter of an inch in the side of the square. Those most generally used for this purpose are in HoPPERs' Practical MeaSurer. In measuring standing timber the length is taken as high as the tree will measure 24 inches in circumference, less than which measurement is not considered as timber. At half this height the measurement for the mean girth of the timber in the stem of the tree is taken; one-fourth of this girth is assumed to be the side of the equivalent square area. The buyer has in general the option of choosing any spot between the buttend and the half-height of the stem as the girding-place. All branches, as far as they measure 24 inches in girth, are measured in with the tree as timber. An allowance, which varies according to circumstances, is generally deducted for the bark. In oak it is from about one-tenth to one-twelfth of the circumference at the girding place; in other sorts of timber it is less. In all, however, this allowance depends much upon special agreement. It is usual to speak of timber by the load, which means 50 cubic feet of squared timber, or 40 cubic feet of rough timber. A load of plank is dependent upon its thickness. Thus, it will require 200 square feet of three-inch plank to make the load of 50 cubic feet; therefore, the load of plank is the number of square feet of its respective thickness which is necessary to make the load of 50 cubic feet. Deals are measured according to their thickness and lengths, by the hundred, reckoning 120 to the hundred.

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WE are indebted for the following summary to the monthly Chemist and Druggist, London, 1861.-Eds. M. M.

Aloexy LUM.—One of the two sorts of Calambac, Eaglewood or Lign Aloes, a fragrant substance, more grateful to Oriental nations than any other perfume, is the produce of the species Agallochum. Lou REIRo states that it consists .."a concretion of the oily particles into a resin in the centre of the trunk, being brought on by some disease of which the tree ultimately dies. It is said to be stimulant, corroborant, cephalic and cardiac, and its scent is stated to be employed against vertigo and paralysis. BAPHIA.—The dyewood, known under the name of Camwood or Barwood, is the produce of the species Nitida. It is stated to be employed, in conjunction with sulphate of iron, in the production of the dark red color of the English Bandana handkerchiefs. BAUHINIA.—Fibers which are employed for the purpose of making ropes are obtained from the species Parviflora, Racemosa and Vahlii. A brownish-colored gum is said to be produced by the species Emarginata and Retusa. The buds and dried flowers of the species Tomentosa are said to be employed by the Indian practitioners in dysenteric affections. An astringent bark is yielded by the species Variegata, which is used in medicine, and also for dyeing and tanning leather. Various other species are reported to be employed in Brazil for their mucilaginous properties. CEs ALPINEA.—Braziletto-wood, which yields fine red and orange colors, is said to be the produce of the species Braziliensis. Brazilwood, employed for dyeing red, rose-color and yellow, is stated to be yielded by the species Crista. Nicaragua, Lima or Peachwood, employed for dyeing red or peach-color, is produced by the species Echinata. The exact species yielding these three dyewoods cannot, however, be said to have been yet determined with certainty. The wood of the i. Echinata is stated to possess tonic properties. The legumes of the species Coriaria, “the Libidibi, or Divi-divipods,” furnish us with one of the most astringent substances known; they are extensively employed for tanning purposes. The roots of the species Moringa and Nuga are said to be diuretic. An oil is stated to |. obtained from the species Oleosperma. The legumes of the species Papai, termed Pi-pi, are emloyed for similar purposes to those of the species Coriaria, but are very inferior to them. The Bukkum, Bookum or Sappan-wood of India, used for dyeing red, is the produce of the species Sappan. The root known as Sappan-root, or yellow-wood, is employed for dyeing yellow. CAssi A.—The seeds of the species Absus are very bitter, and somewhat aromatic and mucilaginous. They are employed in Egypt as a remedy for ophthalmia, under the title of Chichon, or Cismatan. The bark of the species Auriculata is stated by Roxburgh to be employed in medi

cine, and for the purposes of tanning and dyeing leather ; the flowers are said to be used for dyeing yellow. The pulp of the fruit of the species Fistula (Cathartocarpus Fistula) possesses purgative properties, and is officinal in our pharmacopæia. That of the species Braziliana, which is probably only a variety of the above, has a larger, longer and rougher fruit. It is employed in veterinary medicine, under the title of Horse Cassia, and possesses similar properties. The several kinds of Senna met with in commerce consist of the leaflets of various species, but the exact species yielding some of them cannot at present be said to have been accurately determined. The species Officinalis var. Lanceolata, and the species Obovata, are generally considered to be the source of the Alexandrian Senna. The common East Indian, Mecca or Bombay Senna is considered by Royle to be the produce of the species Officinalis var. Acutifolia. PEREIRA attributes it to the species Elongata of LEMAIRE, while Forskal states it to be from the species Lanceolata of Forskal and LINDLEY. Tinnevelly Senna is said to be furnished by the species Officinalis var. Elongata. (C. Lanceolata of Royle.) These are the three kinds which are officinal in our pharmacopeias, and are generally employed in this country. Alexandrian Senna is frequently adulterated with the leaves of Solenostemma (Cynanchum) Argel. Nat. Ord. Asclepiadaceæ. The Asclepias, or Milkweed order, Tephrosia Apollinea. Nat. Ord. Leguminosæ, &c. These sophistications may at once be detected by the leaflets being equal-sided at their base, whereas the Sennas are all unequal. Tripoli Senna is stated to be the produce of the species Ethiopica, American of the species Marilandica, and Aleppo of Obovata.

CERATONIA.—The fruit of the species Siliqua, known as Carob, Locust, Algaroba Bean, St. John's Bread, possesses a sweet, nutritious pulp, supposed by some to have been the food of St. John in the wilderness. It is said to be used in the south of Spain as a food for horses, and is now imported into this country as a food for cattle. Singers are said to chew it for the purpose of improving their voice. The seeds are stated to have been the original carat weights of the jewellers.

CODARIUM.—The fruit of the two species Acutifolium and Obtusifolium, known as Brown and Velvet Tamarinds in Sierra Leone, have an agreeable pulp, which is eaten.

COPAIFERA.-Several species of this genus, if not all, furnish the oleoresin known as Balsam of Copaiba, the quality of which, probably, varies with the species. Among the principal species are probably Coriacea, Langsdorfii, Multijuga, Officinalis, &c. The species Bracteata and Pubiflora furnish the Purple-heart or Purple-wood of Guiana, which is largely employed for mortar beds and the manufacture of musket ramrods.

DIALIUM.—The species Indicum yields a fruit having a delicate, agreeable pulp, less acid than that of the Tamarind. It is termed the Tamarind Plum.

Eperua.—The species Falcata is the Wallaba tree of Guiana, which, according to Sir R. SCHOMBURGHK, yields a very durable wood, of a deep red color, frequently variegated with whitish streaks. The bark is bitter, and is stated to be used by the Arawaak Indians as an emetic.

GLEDITSCHIA.—The species Triacantha yields a fruit similar to that of the Ceratonia Siliqua. In North America it is termed the Honey Locust.

GUILANDINA.-The species Bonduc, or Nicker tree, yields a bitter tonic

bark. The seeds are very bitter, emetic and tonic, and the leaves are stated to possess discutient properties. HAEMAtoxylon.—The species Campechianum yields the wood commonly known as Logwood, employed in medicine as an astringent and tonic, and also for dyeing and other purposes. It contains two crystalline coloring principles, haematin and haematoxylin. HyMENGEA.—The species Courbaril, West Indian Locust tree, is supposed to yield Gum Anime, or East Indian Copal. The inner bark is stated to possess anthelmintic properties. The fruit contains a mealy substance, which is sweet and pleasant; when boiled and allowed to ferment it is said to form an intoxicating drink, resembling beer. The timber is close-grained and tough, and is employed by ship-carpenters for planking vessels, &c. The species Verrucosa probably yields some of the East Indian Copal. A species of this genus probably yields Mexican Copal. Brazilian Copal is thought to be furnished by several species of this genus, and by Trachylobium Martianum, a plant belonging to the same sub-order. Several species of the genus, together with Guibourtia Copallifera, are probably i. source of the substances known as African Copal, African Yellow Gum and African Red Gum. MoRA.—The wood of the species Ercelsa, a large tree, a native of Guiana, is largely employed for ship-building, under the name of Morawood. PARKINsonIA.—The stems of the species Aculeata furnish useful fibers. PoinciaNA.—The leaves of the species Pulcherrima are stated to possess purgative properties, and the roots are said to be tonic. SwartziA.—A powerful sudorific, known as Panococco Bark, is obtained from the species Tomentoso; the wood is stated to be very hard and intensely bitter. The seeds of the species Triphylla are stated to be excessively acrid. TAMARINDUs.—The fruit of the species Indica constitutes the wellknown Tamarind, which, when preserved with sugar, forms a very agreeable confection. The pulp is acidulous, sweet and agreeable, and is an officinal article in the Materia Medica of our pharmacopoeia. It is employed in the preparation of a cooling, laxative drink.

SUB-ORDER MIMoSEAE.

GENERAL PROPERTIES.—The production of gum and the presence of astringent principles are the chief characteristics. Some possess emetic qualities, a few are stated to be purgative, and a small number are reputed to be poisonous.

PRINCIPAL PLANTS AND Uses.

AcAcIA—The various varieties of gum are obtained from this genus. Gum Arabic is principally obtained from the species Vera and Nilotica of DELILE. The species Arabica and Speciosa yield East Indian Gum; the species Affinis, Decurrens and Mollissima, South Australian ; the species Karoo, Cape ; and the species Adansonii, Seyal, Vera, Verek, &c., Gum Senegal. The gum of one of the species is stated to constitute an important article of food to the natives of the Swann River. The wood of the species Arabica is employed in India for making wheels and tent-pegs, and its bark is reputed a powerful tonic, and, together with that of the species Catechu, is extensively used under the name of Babool. The powerful astringent substance known as Cutch, or Catechu, is an extract obtained from the duramen or heart-wood of the species Catechu. It is largely employed for dyeing and tanning, and constitutes one of the officinal substances of our pharmacopoeia. The flowers of the species Farnesiana are very fragrant, and yield, by distillation, a delicious perfume, to which powerful virtues have been ascribed. The wood employed in the construction of the stairs of the Crystal Palace in Hyde Park, at the Great Exhibition of 1851, and which, on its removal, was found to be but little worn, was the produce of the species Formosa, a native of Cuba. It is very hard, tough and durable, of a dull red color, and termed Sabicu. An intoxicating liquor is said to be prepared in India, by distilling the bark of the species Ferruginea and Leucophaea with jagghery water. The bark of the species Melanorylon, a native of Aus. tralia, is sometimes imported, under the name of Acacia Bark. An extract of the bark, very valuable for tanning, is frequently imported. Another astringent product for tanning purposes is that imported under the names of Neb-neb, Nib-nib, or Bablah ; it consists of the dried legumes or pods of the species Nilotica. The species Seyal is probably the Shittah tree, or Shittam-wood, of the Bible. The species Varians is said to be poisonous. Several species are much prized in our gardens for the beauty of their blossom and foliage. ADENANTHERA.—A dyewood is yielded by the species Pavonia, called in India Ruktachundum, or Red Sandal-wood. (This must not be confounded with that produced by the Pterocarpus Santalinus.) The seeds are of a bright red color and perfectly smooth, and are said to be em. g." under the name of Barricarri Seeds, in the northern parts of outh America, for making necklaces, &c. ENTADA—According to HoRSFIELD, the species Pursaetha, of Java, is emetic. The large brown beans are termed Gela, and are used by the natives for washing their hair. ERythophloeUM.—The species Guineense is the Sassy tree of Western Africa. It is used in certain parts of Africa, under the name of Ordeal Bark, or Doom Bark, as a supposed test of the innocence or guilt of persons suspected of great crimes, as secret murder, &c. INGA.—The pods of the species Faculifera, or Poix Doux, of St. Domingo, contain a sweet pulp, having purgative properties, which is used by the natives. Similar qualities are stated to reside in the pulp of the pods of the species Vera, and that of Tetraphylla is sweet and mucilaginous. The species Vera possesses astringent properties. MIMosA.—The root of one of the Brazilian species is stated to possess poisonous properties. The roots of the species Sensitiva are said to evolve a most unpleasant odor, resembling that emitted from sewers in time of impending rain. PARK1A—The seeds of the species Africana are stated to be roasted in the same manner as coffee, bruised, and allowed to ferment in water; when they begin to become putrid, they are well washed, pounded, and made into cakes in a similar fashion to chocolate. They are stated to be an excellent sauce for all kinds of meat. A pleasant drink is formed from the farinaceous matter surrounding the seeds, and a sweetmeat is also made from it.

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