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whole weighing 62 pounds, strapped on the fore part of the saddle. The person thus equipped is supposed to be enabled to travel with expedition to the aid of ships in danger of being wrecked on parts of the coast intermediate to the mortar stations; and with this small apparatus, the log line is to be projected over the vessel in distress, from which a rope should be attached to it to haul the crew on shore. Captain Manby caused the howitzer to be dismounted from the horse, and in a few minutes fired it, when the shot was thrown, with the line attached, to the distance of 143 yards.

"At a subsequent trial the horseman, fully equipped, travelled a mile and a third; the howitzer was dismounted, and the line projected 153 yards, in six minutes." P. 32.

In order more fully to explain the mode of operation, we have gone a little out of our way on this occasion, to lay before our readers a sketch of the apparatus in full activity.

[graphic]

Such is the simple but efficacious nature of Captain Manby's first invention; and a few practical experiments soon ascertained the allowance to be made in pointing the mortar to windward of the object over which the rope is to fall, in order to obviate the effect of a strong wind, which would, of course, carry it considerably to leeward.

Experience also proved, that the mortar should be laid at a low elevation, in order to ensure the certainty of the rope's falling on the weathermost part of the rigging.

This original invention, however, was obviously capable of many improvements. The first of which was to afford assistance to vessels whose crews, either from their being lashed to the rigging,

or from extreme cold and fatigue, are incapable of assisting to secure the rope to the wreck when projected over it from the mortar. This was attained by adding a quadruple barb to the shot, by means of which, when the rope is hauled tight by the people on shore, one end is firmly secured on some part of the rigging or wreck, and a boat can of course be hauled to the relief of the crew, without any assistance on their part.

The following is one of the many certificates of the practical benefits that have resulted from this improvement:

"WE, the crew of the brig, Nancy, of Sunderland, do hereby certify, that we were on board the said vessel, when she was stranded on the beach of Yarmouth, on Friday morning the 15th of December, 1809, and compelled to secure ourselves in the rigging, to prevent being swept away, the sea running so high over the vessel. And we do further declare and certify, that Captain Manby firing a rope with a hooked shot securely holding on the wreck, enabled a boat to be hauled from the shore over the surf to our relief, otherwise we must inevitably have perished." P. 24. Signed by six persons.

Ships are also stranded by night more frequently than by day, and generally in dark and boisterous nights; and to wait till daylight for the application of this apparatus might of course eventually preclude all its benefits.

The weather, also, upon an open coast, during a storm, is seldom favourable for the inflammation of gunpowder; and some attempts to save the lives of the shipwrecked had actually failed from the wetness of the powder and the difficulty of keeping a portfire burning. Captain Manby at first attempted to obviate this last inconvenience by the use of a pistol lock and short barrel; but he found the following ingenious contrivance by far the most efficacious mode of securing a discharge: A short funnel-shaped tube of common writing paper is filled with a preparation of gunpowder, and stuck into the touch-hole of the mortar; and Captain Manby carries in his pocket a small phial of

liquid, with which he wets the end of his finger, and applying it to the gunpowder, tube, produces instant inflammation and a discharge of the mortar, even in the wettest weather. We believe that there are several preparations known to chemists which will produce this effect; but this by no means detracts from the merit of Captain Manby's application of one of them to this specific and beneficial purpose, or weakens his claim to the merit of any advantage which the general service may derive from discharging battering artillery in the same manner. As we have had occasion more than once to observe in the case of Dr. Bell and others, it is not the mere inventor of an insulated fact, converted to no purpose of practical utility, that has a just claim upon the gratitude of mankind, but he who converts an object, but little known or little used, to new purposes-and his claim is great, exactly in proportion to the extent of the advantages derivable from the nature of those purposes.

The preservation of human life from sudden and violent termination is an object of the highest importance, both with a view to policy and humanity. But when the exertions for such a purpose are occupied on behalf of our fellow countrymen engaged in the sea service, of men who expose their lives to double risk, to the storm and to the battle, for the comfort and safety of those who sit at home-they are doubtless at least doubly interesting. And though we are far from wishing to derogate from the portion of credit due to the prosecution of science for any facilities that may be offered, we must strenuously insist that the man who first converts scientific discoveries to noble purposes of practical utility, not previously in the contemplation of philosophers, has a just and fair claim to the title of an original inventor.

It now remains that we explain to our readers the ingenious method by which Captain Manby contrived to extend the assistance (afforded by his first invention to ships stranded in the daytime,) to those wrecked even in the darkest nights. The requisite objects were,

1. First, to devise the means of discovering precisely where the distressed vessel lies, when the crew are not able to make their exact situation known by luminous signals.

2. Secondly, to discover a method of laying the mortar for the object with as much accuracy as in the light.

3. Thirdly, to render the flight of the rope perfectly distinguishable to those who project it, and to the crew on board the vessel, so that they cannot fail of seeing on what part of the rigging it lodges, and consequently may have no difficulty in securing it.

To attain the first object, a fire ball is used, such as is often thrown up in the attack and defence of fortified places to discover the situation of an enemy by night-and such as was in fact used by the French at the late siege of Badajoz to discover the exact situation of our storming parties in front of the breaches. It consists of a hollow ball of pasteboard, having a hole at top containing a fuse, and filled with about fifty luminous balls of star composition, and a sufficient quantity of gunpowder to burst the ball and inflame the stars. The fuse is graduated so as to set fire to the bursting powder at the height of 300 yards. On the stars being released, they continue their splendour while falling for near one minute, and strongly illumine every surrounding object: ample time is therefore allowed to discover the situation of the distressed vessel.

During the period of the light, a board, with two upright sticks at each end, (painted white to render them more discernible in the dark) is pointed towards the vessel, so that the two white sticks shall meet in a direct line with it, the wreck being a fixed object. This will obviously afford an undeviating rule by which to lay the mortar, making an allowance, as by daylight, for wind, &c. Thus the second object is attained.

For the third, a shell (instead of a shot) is affixed to the rope, having four holes in it to receive fuses, and the body of the shell is filled with the fiercest and most glaring composition, which when inflamed, displays so splendid an illumination of the rope, that its flight cannot be mistaken. We insert a sketch of this contrivance, and add a certificate of the success of the whole operation in practice.

[graphic]

Report of experiments made thereon, before a committee of colonels and field officers of the royal artillery at Woolwich, on the 3d of May, 1809, by order of the honourable Board of Ordnance.

SIR, Royal Arsenal, Woolwich, May 3, 1809. "I REQUEST you will inform the master general and the right honourable board, that in obedience to their orders, communicated in your letter of the 29th ultimo, the committee of colonels and field officers, named in the margin *, assembled on the following day, to witness the further experiments proposed by Captain Manby, with a view of obtaining a communication from the land with stranded vessels.

"On this occasion Captain Manby exhibited his contrivance for ascertaining the position of a ship stranded during the night-time, by projecting light balls into the air, from a mortar at a high elevation, by which means obtaining a momentary view of the object, its situation is instantly and determinately marked, by placing two upright sticks, fixed on a short plank, which can be moved with the greatest facility in the exact direction, and by which the mortar can be laid with precision, in the usual manner.

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Captain Manby then exhibited a contrivance to insure the firing of the mortar in wet or stormy weather, by means of a short pistol, the lock of which is so covered by a tin box as to exclude the effects of the wind or rain on the priming.

"The next experiment was to prove the practicability of throwing a life rope attached to a shot from a 12-pounder carronade, and the application of a shell with several fuzes, instead of a shot for the same purpose, at night, so that the crew on board the stranded vessel, by the brilliant light of the fuzes, could not fail to see the projection of the rope to their assistance.

"I am happy to report to his lordship and honourable board, that Captain Manby's experiments were perfectly satisfactory to the committee, and they have no doubt of their successful application to the noble purpose he has in view.

"I have the honour to be, &c.

To R. CREW, Esq. Secretary to the Ordnance.

VAUGHAN LLOYD, Col. Com. Lieut. Gen." P. 64.

Such are the most prominent and interesting facts relating to Captain Manby's discoveries for the preservation of shipwrecked seamen. There are many minor points, respecting the mode of bringing the sick on shore, of carrying a boat over a surf, to reach a vessel stranded without a bar, &c. &c. to which we have not time to refer, but which are described and illustrated by wood cuts in the work before us. Among these we are particularly struck with his simple method of converting any common boat into a life-boat, at an expense of about 37. by merely lash

Present-Lieut. General Lloyd, Colonel Ramsay, Lieut. Colonels Bothwick, Riou, and Charlton; Majors Viney, Waller, Griffith, and Dixon.

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