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the merchant, the ship-broker, the factor, the manufacturer, the packer, and the lighterman.

Among merchants, there are Spanish merchants, Turkey merchants, Italian merchants, Russia merchants, Hamburgh merchants, West India merchants, American merchants, Brazil merchants, and African merchants.

XI. The Art of Navigation.

215. That must be allowed to be a most useful as well as an extraordinary art, which enables men to conduct great ships with precision, across vast seas many thousand miles wide, in which they often sail for months together without seeing any land to guide them in their course.

216. Anciently, and indeed till within the last 400 years, ships seldom ventured out of sight of land; and if they did, it was by mere accident that they ever regained the shore: such were the disadvantages of the Egyptian, Phoenician, Carthaginian, Roman, and Grecian commerce.

217. About the beginning however of the 14th century, a new æra was produced in this most noble and useful of all the arts, by the discovery, or perhaps more properly, the application of the properties of the Load Stone. This substance is a species of iron ore, or ferruginated stone, which is foound, generally in iron mines, and of various forms, sizes and colours, and has not only the property of attracting Iron and Steel, but the more extraordinary one of pointing always towards the

north pole of the earth, and in that state, it is called a natural magnet. It has also the property of imparting its virtue to a bar of Iron or Steel, which is then called the artificial magnet or magnetic needle, and which being properly balanced and fitted up, forms the mariners compass. With this instrument, the navigator can now always shape his course with correctness and safety, over all the oceans of the earth.

Obs. Considerable controversy and uncertainty has subsisted in relation to the discovery of the Load Stone and mariners compass, and various nations have contended for the honour of it. Some learned writers assert, that it was known to the Chinese above a thousand years before the Christian æra. It is certain that the Load Stone was known to the ancients before the time of Plato and Aristotle, as its properties are referred to in their works. But it appears, that they were only acquainted with its capacity of attracting and repelling iron, and not at all with its polarity or always pointing towards the pole of the earth. Among the moderns, this discovery has been claimed by the Neapolitans, the Venitians, and the French. It has been generally ascribed to the first of these, the (Neapolitans) but however, this may be, it was not until about the 14th century, that the mariners compass as it is now constructed was adopted into general use, and which has since been greatly improved under the denomination of the Azimuth Compass.

218. As the compass enabled him to keep an account of the course of his voyage out, so it was not difficult to retrace the same course back by referring to his journal. If a man in the dark, go 50 steps to the right, 20 strait on, and 30 to the left; he will easily return to the place whence. he set out, if he take 30 steps to the right, 20 strait on, and 50 to the left.

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219. In the wide and pathless ocean, therefore this instrument proves a certain guide to the mariner and enables him, if he has recorded his past course correctly, to ascertain his exact position at all times on the sea, and to shape his future course accordingly.

220. In the construction of the compass, the magnetic needle is usually placed in a frame, and covered by a glass. Beneath it, in the frame, are marked the 32 points of the compass; that is to say, the whole circle of the horizon is thus divided into 32 parts.

The principal of these are, the four cardinal points, the north, south, east, and west; and these are subdivided into north-east, north-west, south-east, and south-west, &c. &c.

Obs.-Annexed is the representation of this division; the boxing or repeating of which is, among young sailors, deemed a conisderable achievement.

221. The practice of navigation led, however, to various other discoveries; which now render the mariner's compass not the only guide to the navigator, except, during a series of cloudy weather.

Every child can always tell where he is, by looking at objects out of himself: i. e. at the houses, trees, and places, to which he is accustomed.

So it is with sailors: there are certain fixed objects out of the earth, as the sun, moon, planets, and stars; and by the position of these, a skilful sailor with the aid of his instruments can always ascertain his true situation.

222. If it appear by the nautical almanac, that the sun is, on the 5th of June, at London, 61 degrees high at 12 o'clock, and a sailor, by his quadrant, finds it at that time to be 70 degrees high, he concludes that he is pine degrees, or 625 miles, nearer to the vertical place of the sun, or more to the south than London.

223. If it appear by the almanac, that at ten o'clock on the evening of June 5, that the moon comes to a conjunction with the planet Mars, at Londen, and a sailor find that the conjunction takes place at nine o'clock where he is, he concludes that he is one hour, or 15 degrees, or 1045 miles west of London.

224. The nautical almanac is a work published annually by the British government expressly for the use of navigation. It consists of tables and calculations, shewing the positions and motions of the heavenly bodies and their various relations to each other, by means of which, the navigator with

his quadrant, or sextant, and a good watch or time piece, can now ascertain his position in any part of the ocean within a few miles. Several American editions of this most useful work, have been published with important additions and improvements, for the facility of navigation.

225. So expert are navigators become in our days, that a ship has sailed from Portsmouth to Calcutta in 55 days, and from Batavia to Philadelphia in 78 days, voyages which formerly employed six months; from Portsmouth to Malta in 11 days, formerly two months; to New York in 21 days, formerly two months; and to the West Indies in 21 days, formerly two months.

Drake and Anson were three years in sailing round the world; and this is now frequently performed by merchantmen, in nine or ten months.

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