WHILST we are doing all in our power to guard our coasts with life-boats ready to save life in the event of a vessel being stranded on our shores, we must not lose sight of the fact that the greatest loss of life among our own countrymen, during the past two years, has arisen from the difficulty of getting the ship's own boats lowered down in safety when the vessel has got into danger. In the case of the Orion, with 200 persons on board, of whom 160 were passengers, while running along the coast of Scotland in a calm summer's night, and within hail of the shore, she struck upon a rock off Portpatrick, and sunk in deep water, when 40 of the crew and passengers were drowned. In the more re- cent case of the Amazon, which caught fire on the 4th January of this year, at 100 miles distance from the Land's End, only 86 hours after leaving Southampton, " the mail- boat on being lowered was immediately swamped, with about 25 people in her, all of whom were lost; the pinnace sheered across the sea before the people in her could unhook the fore-tackle, and was dragged through the water at such a rate that everybody was washed out of her; while clearing away the second cutter, a sea struck her, raised her off the cranes, and unhooked the bow tackle; the fore end immediately fell down, and the people in her were precipitated into the sea and drowned; **—and thus, from the want of the means of lowering the boats in safety, 99 persona perished. In the still more recent case of the Birksnkeatl troop-ship, wrecked on the morning of the 26th Fe- bruary on the coast of South Africa: out of 638 gallant fellows, vho left Simon's Bay a few hours before, only 184 remain to tell the tale. In all these cases, and in many others that might be cited, could the boats inboard, the paddle-box boats,, and the quarter-boats have been promptly and safely got afloat, there can be no doubt that numbers of lives would have been saved, Strongly impressed with this conviction, Mr, STIRUHQ LACOS, formerly an officer in the East India Company's service, has pro- posed a plan for lowering boats at sea with safety, even when the vessel, as in the case of the Amazon, was going rapidly through the water. This is no theoretical plan, but has been actually put in practice on board one of the steamers of the South-eastern and Continental Steam-packet Company on the 5th August last, off Folkstone, as witnessed and certified to by Vice-Admiral TUCKER, K.C.B., and Captain GEORGE HATHORN, E.N., and many others who sign the certificate, when one of the quarter- boats, with Mr. LA.COS and a crew in her, was lowered into the water by one man, and went safely clear of the ship in a strong south-west breeze, and the steamer going at full speed, or at the rate of 12 miles an hour; and this experiment was repeated five or six times with similar success. We trust that this trial may be considered so far decisive, as to induce those who have hitherto been incredulous or wavering be- tween this and three or four other plans that have recently been brought before the public, to go and witness a trial, and be convinced of the simplicity and practicability of the arrangement.

The characteristic feature of Mr, LACON'S plan is, that the boat is suspended from the davits, by pendants (or single ropes), instead of the usual tackles, the inner ends of which are brought round barrels at either end of a horizontal bar of iron (or windlass), secured close to the side of the vessel, either within or without the bulwark ; the inner end of each pendant has a Flemish eye worked in it, and is merely hooked over a pin on the barrel, so that as it is unwound it runs off clear and disengages itself. A friction brake or strap is applied to the windlass in the centre, and worked by one man, by means of a lever 3 feet long, just as weights are lowered by a crane; the boat therefore must go down equally or evenly, can be stopped in its descent at pleasure, or both ends can be let go at once. It will be observed that this plan, so far, only provides for lowering a boat safely at sea, not for hoisting her up again; and in this Mr. LACON has shown Ms judgment, as the former was the real problem to be dealt with, and we believe he has solved it effectually. To hoist the boat up at sea, the common tackles must be used; the pendants do not interfere with them, as the tackles can be hooked to an eye-bolt at the end of the davits, and worked as before. But when short of hands, in moderate weather at sea or in harbour, two men can hoist the boat, up by means of the inner rim of a ratchet-wheel, the friction pulley or brake acting as a pawl The great convenience of this arrangement in all merchant vessels, but especially in short handed steamers, need not be insisted upon The most critical position for a boat on being lowered is when, halfway down, wave rises under her bow, and unhooks the foremost tackle; in such a case the brake would be thrown back immediately and the after-end would go down as fast as the foremost, as the weight of the boat would immediately overhaul the pendant, and the boat would be free.

The only plausible objection we have heard to this plan is that in a ship-of-war the windlass or winch might be in the way of two of the quarter-deck or poop guns, and that the iron bar would be an additional danger in time of action, and, if struck, might act as a bar-shot. This is admitted, as far as the objection goes, but, first, we are not at war with any nation, and it may be hoped we shall not be so for some time to come; and, secondly, we are not at present recommending the plan for ships-of-war, but for passenger-steamers, emigrant-ships, and troop-ships, and we hold it to be imperative that they should be at once so fitted. At this moment not less than 100,000 of our countrymen are crossing the Atlantic as emigrants to Canada, the United States of America, and Australia, in ships fitted with the old mode of lowering their boats, whereas the present plan was made fully public in January last. Many of these ships are provided with every luxury; one of the largest and finest that sailed about a month since, advertised that there was on board a " COL- LARD'S grand piano in the saloon!" Grand pianos are very nice instruments, but where hundreds of lives are at stake, we really think " LACON'S safety plan for lowering boats" would or should be a more attractive advertisement. But we trust the affair will not be left to the choice of shipowners; if, as we believe, an effectual remedy for one portion of " the dangers of the seas" has been found, public opinion will shortly force its adoption.