In a place like Greenock, which had so many shipping, it is to be expected that many fearful accidents would occur. The waste of individual life by drowning, or falls from masts, &c., would make a long and melancholy catalogue. But, independent of this, vessels have been wrecked in our own channel; some have been burnt at sea; and others foundered on deep, or been cast away upon foreign lands. But, probably, the most melancholy intelligence which reached this port, was the loss of a number of our vessels on the coast of Portugal. The following are the particulars:-

Copy of a Letter from Captain Gibson, of the Robust, to the Owners here, dated 30 leagues north of Lisbon, 4th April, 1804.

"I am sorry to acquaint you of our melancholy misfortune, which happened on the morning of the 2d instant. At four o'clock we struck the ground, and drove on shore, and about thirty or one-and-thirty more of the fleet, and the Apollo, our Commodore. A great many lives were lost out of the several ships, and the sight is dismal to behold for many miles along shore. All our crew got on shore, without the loss of a man. The Robust is all together, and fast; but the water ebbs and flows in the hold, and the surf is so heavy, renders it impossible for any person to get now near to her; and I do not think any thing belonging to her will be saved, as she will break up in a very short time, and don't expect her to hold fast till to-morrow morning. The accident was merely through neglect of the Commodore. As the Wjnd was from the S.W., there was no occasion to stand so far to the eastward. All the fleet was sensible of being to the eastward, and some of them tacked, when he fired at them to bring them to: but he himself has suffered, with about 200 of his crew, some of whom were on the wreck these sixty hours, without any subsistence. The Clyde ships which have suffered here are the Elizabeth, Gait; the Peggy, Carnochan; Peggy, Bartley; Active, M'Niccol; Fame, Gammel; Albion, M'Ewing; Nancy, Weir; Caledonia; Gilkison; and ourselves. We had much ado to get on shore, as no boat was able to stand the surf. There was a great deal of people lost out of the Clyde ships: some of them upwards of half their crews. There is a British Consul here at present, who came from a town about eight miles off, called Figueiro. I have nothing more to mention at the present time; but I will write you when I get clear of this, which I think will not be for some weeks, as we are to wait here, by order of the Consul, until we all get away together, in a vessel, to Lisbon."

During the war, privateers and letters of marque, owned by Greenock merchants, were very successful; and a number of gallant exploits were performed by our seamen. The ships of war also occasionally visited the place; and, for a considerable time, (on the remonstrance of the Magistrates,) a guard-ship was kept at the Tail of the Bank. The largest class of war vessels seen here, was a 42 gun frigate; and one 74, or line-of-battle ship, came up as far as Gourock. During a war they can be be of little service stationed here; as the most effectual mode of protecting the trade, and also the town, is cruizing in the channel, and meeting the enemy before they reach our doors.

The Coasting trade, though it has diminished, as already mentioned, still gives employment to a number of men, and also to a fair amount of tonnage. The following is a statement for the years 1828 and 1829:-

About 50 years ago, though the Foreign and Coasting trade of the port had increased to a considerable extent, yet a distinct knowledge of the principles of navigation, for making the requisite observations for ascertaining the longitude by lunar observation,- and the latitude by double altitudes of the sun, as practised in the East India trade, was but very imperfectly known. Indeed, no shipmaster from the Clyde had then attempted to reduce it to practice; nor does it appear that any teacher in this country had possessed the requisite means to give instruction to seamen on important branch. The shipmasters of the old school had all prejudice on score; and consequently the rising generation were entirely deprived of the means of practical, as well as theoretical knowledge. Fully aware of the advantage of this branch of education to the trade, Mr. Lamont, shortly after his appointment in 1781, went to London, for the express purpose of obtaining information on the subject, and also the requisite instruments, in order to prove to seamen the absolute truth of what they merely knew by report. It was during the magistracy of the late Roger Stewart, Esq., that an instrument was procured, for the twofold purpose of reducing to practice the principles of geometrical surveying, and for observing, the cotemporary altitudes of the heavenly bodies, required in taking lunar distances by the sextant, which had been already procured by Mr. Lamont, as well as a pocket chronometer, by the late John .Melville. About 1789 or 1790, he also procured Dolland's achromatic telescope for observing the eclipses of Jupiter's satellites; and a planetarium, for illustrating the solar system, with its accompanying tellurian and Lunarian complete. Thus provided, he was in a state for making actual observations, for explaining the lunar theory, and for emulating the Americans, who then frequented the port, and who boasted of their superior knowledge in these matters. The first individual to whom British seamen are indebted for reducing the complete lunar theory to practice, was the late Astronomer Royal, the Rev. Neville Maskelyne, who, after his voyage to Saint Helena, in 1761, planned the Nautical Almanack, and the requisite tables for its use. By others these have been brought to that degree of perfection necessary for the seaman's use. Since that period the famous Rainsden and Trougliton have executed, under the patronage of government, their accurate and expeditious dividing engine; and produced the instruments required.

The first that availed himself of instruction on this subject, under Mr. Lamont, was a Mr. Robertson, about 1788, who used the first metal sextant known on the Clyde, which was made by Jones of London. Mr. Tronghton, after this, invented the light patent sextant, and also the circle of reflection, which has been proved to be of unrivalled use in nautical astronomy. Captain James Hamilton, of the brig Nancy, (cousin to the late Professor Hamilton of Oriental Languages,) was the next who procured a sextant, in 1790, and prosecuted this study with much success.

Lieutenant-General Sir Thomas Brisbane, (then Major Brisbane,) was the first person who sailed from the Clyde with all the requisite instruments for ascertaining his situation at sea with any thing like precision, he had several chronometers; a circular instrument by Tronghton, divided on gold; and a sextant by Dolland. He sailed from hence in the brig Fame, Captain Armour, in 1799. He, and the late Quintin Leitch, then Captain of the brig Clyde, who became an early proficient in such observations, communicated by signal during the whole voyage, and through life a warm friendship existed between them. The late Captain John Udny was among the first who carried, at his own expense, books, instruments, &c., in a complete state, for making lunar observations; and was allowed to have been the most expert lunarian then sailing. Since that time, however, every attention has been paid to this useful branch of education and were it not that some might consider it invidious to notice by name many Captains who are an ornament to their profession, we would most cheerfully give them a place in this simple record. The fair fame they have earned is not the less remembered; and they may rest assured that, thus trying to lessen the tedious monotony of a long sea-voyage, only endears them the more to those who intrust them with their property, as well as the lives of passengers and seamen. It is a situation of all others of deep responsibility. A ship on the ocean is to the master, a little world, quite under his own control ; the happiness and comfort of all under him may be mainly attributable to him; and by his doing all in his power to form the mind of those youths intrusted to him, and by seconding the efforts of the teacher in giving useful information, he confers a greater honour on himself than on those who receive the boon. In this way there would be fewer run-aways from ships, while a wild boy would be generally awed into submission by treatment at once conciliating and kind.