bark. The seeds are very bitter, emetic and tonic, and the leaves are stated to possess discutient properties.

HEMATOXYLON. 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, hæmatin and hæmatoxylin.

HYMENCEA.-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 the source of the substances known as African Copal, African Yellow Gum and African Red Gum.

MORA. The wood of the species Excelsa, 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. is employed in the preparation of a cooling, laxative drink.

SUB-ORDER MIMOSEÆ.

It

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.

genus.

ACACIA. The various varieties of gum are obtained from this 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 Melanoxylon, a native of Australia, 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 employed, under the name of Barricarri Seeds, in the northern parts of South America, for making necklaces, &c.

ENTADA. According to HORSFIELD, the species Pursatha, of Java, is emetic. The large brown beans are termed Gela, and are used by the natives for washing their hair.

ERYTHOPHLEUM.-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.

PARKIA. 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.

JOURNAL OF NAUTICAL INTELLIGENCE.

I. IRON AND WOODEN NAVAL VESSELS. II. IRON SHIPS. III. REVOLVING SHIPS' RIG. IV. NEW PATENTS. V. LIGHT-HOUSE SERVICE IN GREAT BRITAIN. VI. CONTRIBUTIONS TO NAUTICAL SCIENCE. VII. STEAM RAM, DEFENCE. VIII. MASTS OF THE WARRIOR. IX. SHIP GREAT REPUBLIC. X. NAMES OF NEW GUN BOATS. XI. NEW LIGHT-HOUSES.

IRON AND WOODEN NAVAL VESSELS.

ACCORDING to the London Mechanics' Magazine the first question for discussion is the comparative value of iron and wooden ships-of-war. In favor of the latter we have a conservative party represented by Sir HOWARD DOUGLAS, who is probably the ablest living advocate of "wooden walls." It is his opinion "that ships formed wholly, or nearly so, of iron, are utterly unfit for all the purposes and contingencies of war, whether as fighting ships or as transports for troops." In opposition to this opinion Mr. J. SCOTT RUSSELL endeavors, and we think successfully, to establish: 1. That iron steamships-of-war may be built as strong as wooden ships. of greater weight, and stronger than wooden ships of equal weight.

2. That iron ships of equal strength can go on less draught of water than wooden ships.

3. That iron ships can carry much heavier weights than wooden ships. 4. That they are more durable.

5. That they are safer against the sea.

6. That they are safer against fire.

7. That they are much safer against explosive shells.

8. That they are much safer against molten metal.

9. That they are much safer against red-hot shot.

10. That they can be made impregnable even against solid shot.

In a recent paper on the form of ships, by ROBERT DUNCAN, Glasgow, the following proportions for side-wheel steamers are given: Length, equal to ten times the beam; depth, six-tenths of beam; draught of water, seven-tenths of depth, or forty-two of beam; the co-efficient of displacement, fifty-five per cent.

IRON SHIPS.

As Sir H. DOUGLAS has attacked the construction and sailing qualities of the Great Eastern, his opponent first disproves his assertions and predictions regarding her, and then states the facts regarding iron war-ships which have been ascertained by actual experiment. Experience has proved, first, that "when the thickness of a vessel's side is not more than half an inch, shots fired obliquely have glanced off the iron vessel which would have penetrated a wooden ship; second, that shots fired directly have passed through both sides of the ship, doing less damage to the ship directly and less damage by splinters than would have been the case in timber ships; third, that the shot holes have been as easily stopped, and more expeditiously and less expensively repaired than in wooden

ships; fourth, that their plates of wrought-iron, even five-eighths of an inch, are proof against shells; that iron plates four inches and a half thick are nearly impenetrable to shot fired from the heaviest nature of guns; and, finally, that plates six inches thick are practically impenetrable.'

REVOLVING SHIPS' RIG.

The revolving rig of Capt. COLES, of this city, has just been applied to the square sails of the bark Liverpool, now lying at the dock a short distance from the Grand-street ferry, East River. The sails by this are worked from the deck; not a man is required to go aloft. A long roller is suspended in brackets connected with the lower yard, and the sail is wound up on this roller by revolving it with ropes or chains from the deck. The sail is rolled up exactly like a piece of cloth on a weaver's beam, and any amount of its surface can easily be taken in or exposed as required. This rig is exceedingly snug, and although the Liverpool (now somewhat old) is the first vessel to which it has been applied in this port, those who command her believe it will operate well, and save a great amount of labor, while it ensures greater safety. Such sails can be operated more rapidly than those which are rigged by the common method.

NEW PATENTS.

For an improved spring tackle for the sheets of fore-and-aft rigged vessels. WILLIAM WOODBURY, of Gloucester, Mass., patentee.

Mr. WOODBURY claims the spring B., in combination with the traveller C., and sheet E., operating substantially as described, for the purpose specified.

For an improvement in safety ships. E. S. WILLSON, of Saratoga Springs, New-York.

Mr. WILLSON claims a refuge cabin in combination with the layers of cement and water bed, air boxes and device for ventilation-the whole constructed and all its parts arranged substantially as specified.

For an improved life-boat. J. T. SCHOLL, of Port Washington, Wis

consin.

Mr. SCHOLL claims, first, the cylindro-conical life-boat constructed of separate slats, hinged together and capable of folding up, in combination with a water-proof fabric and metallic sheathing.

Second, he claims, in combination with the cylindrical part of the boat, the hinged folding heads.

This invention and improvement in life-boats consists, first, in constructing the body or hulk of the boat in the shape of a cylinder, terminating at each end in a cone, said cylinder and cones being made up of slats or staves which are covered on the outside with a suitable water-proof fabric and also with metal plates, all of which are jointed and hinged together so as to be water-tight, and to admit of being folded up. It also consists in two hinged heads capable of being folded up with the boat, which are within each end of the cylindrical part of the boat, and acted upon by springs, which springs and heads operate to prevent the boat from collapsing while in the water, and to keep the boat in a proper condition to carry passengers. It also consists in a revolving spring arm arranged on

the propeller shaft, in conjunction with certain spring valves which cover port-holes or ventilators through the cylindrical part of the hull, said arm being made to open the valves when the parts are above water. It also consists in a rolling carriage or platform furnished with seats for passengers, and arranged within the boat in such a manner that the boat or hull thereof will revolve independently of said platform.

THE LIGHT-HOUSE SERVICE OF GREAT BRITAIN.

According to the London Times, the authorities constituting the lighthouse administration of the kingdom are computed to be 174 in number. Of these about 170 are local authorities, empowered by various charters or customs to superintend the lighting and marking of coasts, rivers or harbors at particular spots. Then come three general authorities-the Trinity-house for England and Wales, the Commissioners of Northern Lights for Scotland, and the Ballast Board of Dublin, for Ireland. Lastly, there is the Board of Trade, which, by a recent act, requires certain prerogatives of chief control. In respect of the distribution of power, it may be observed that the Trinity-house has some authority over the Scottish and Irish boards, and the Board of Trade a controlling authority over the Trinity-house. In connection with this department, too, the general authorities have certain powers over local authorities, but they are not very commonly exercised or very extensively applied. Indeed, it is not to be supposed from enumeration that there exists any complete chain of responsibility or graduation of power. No such system prevails. It is true that the ultimate appeal lies apparently to the Board of Trade, and that board seems to have concerned itself actively with the finances of the service, but to have been rather more solicitous about economical administration than immediate inspection or superintendence. Such being the number and nature of the boards engaged, it is now necessary to say something about their constitution, and, for the sake of conciseness, we had better explain what elements they lack than what they comprise. In no one of the four governing bodies, though they are all differently constituted, is special knowledge of the subject exacted as a qualification for membership. The elder brethren of the Trinity-house having been mariners by profession, have certainly a general knowledge of the sea, but not necessarily any thing more. The Scottish board is principally recruited from the legal profession, the Irish board from a mercantile and commercial circles. As for the Board of Trade, it is, of course, notorious that its members, however able, are not selected for their acquirements in optical engineering, and of the whole matter the commissioners observe that "the government of light-houses in the United Kingdom, their management and construction, are all confined to bodies of gentlemen of various employments, none of which necessarily afford them an opportunity of acquiring a knowledge of those branches of science which bear upon light-house illumination." Very different is the state of things in other countries. In France, of course, the organization is perfect. There "lights are placed on a system that their lights should cross. They are inspected on system-the size of the flame, the quantity of oil to be consumed in an hour to produce a good light, the minutest detail is provided for and calculated to a nicety, and