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DESCRIPTION OF A WATER-HORSE ELECTRICAL TELEGRAPHS.

DESCRIPTION OF A WATER-HORSE.

SIR,It is good sometimes to unbend, and study the agreeable. I present you, therefore, with a drawing of a Water-Horse, which I have constructed. The body of this aquatic steed is a frame of wood, covered with canvas. The canoes, six feet long, are composed of skin stretched on a frame, and made perfectly watertight above and below. The motion is communicated to the paddle-wheel by a strap passing over a wheel in the shoulder, turned by either hand with a wince. A rudder is affixed to each canoe, and connected by an iron rod to a cross-beam which passes beneath the horse, and, moving on a pin at the centre, with a stirrupleather at each side, serves at once to support the feet and work the rudders.

The manner of steering is shown in Fig. 2, where the beam is seen connected to the arms, AB, placed at right angles to the rudders, CC; so that when the right foot is pushed forward, the arm, B, advances, and A recedes, thus making the rudders form a correspondent inclination, or, simply, the motion, is just that of the hammer-lever.

Very agreeable equestro-aquatic excursions might be taken on the back of this floating Hippopotamus, and, perhaps, by means of your valuable miscellany, we shall shortly have the satisfaction to find that we have added one more to the novelties and amusements of the age.

I remain, Sir,
obedient servant,
THOMAS H. BELL.

Your very

Alnwick.

ELECTRICAL TELEGRAPHS.

SIR, If the following hints on the subject started by your Correspondent, "Moderator," should be worthy of notice, their insertion in your valuable work will oblige a constant reader.

To whatever length the conducting wires have been extended, and, if I mistake not, experiments have

been made to the extent of nine miles, the shock has invariably returned, without any perceptibie loss of time. If the same results will hold good to the distance of several hundred miles, and I see no reason to doubt it, it is, of all known means, the best calculated for telegraphic dispatch. The great number of stations at present necessary would be reduced to one at each extremity; and, what is of more importance, the communications may be made by night or by day, in hazy or clear weather.

The method of working may be, I imagine, effected by the following simple means:The present telegraphic communication is effected by means of six shifting boards, in a manner with which your readers are doubtless conversant. Now, if it be practicable to lay down one wire, it will be equally practicable to lay down six; and the cost of the wire would be nearly all the difference in the expense. Let the wires terminate in a dark room. On one wall let there be the figures, 1, 2, 3, 4, 5, 6, prepared in tinfoil, according to the method practised by electricians, in forming what are called ·luminous modes und figures. Bring the six wires in contact with the six figures separately. With this contrivance, all the signals may be performed, as at present, with six shifting boards. A shake of the arm, as Moderator suggests, may call the watch to his duty; and he could name the signals, as they appear, to his assistant, as is the present custom in the established telegraphs. His assistant must, of course, be separated from the dark room by a slight partition, that should be proof against light, but not against the full hearing of the human voice. Her.

These few hints, Mr. Editor, may serve as food for reflection to some of your readers who are fond of novel improvements. Should you think the subject worthy of notice, I will explain, at greater length, at somé future time.

I am, Sir,
Yours, respectfully,
R-

CASE OF THE SHIPWRIGHTS-USE OF THE SLIDING RULE. 179

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SIR,-Being one of a numerous class who have lately suffered much inconvenience, as well as loss, by the combination of Shipwrights for increased wages, it may not be amiss to show, through the medium of your publication, the injurious consequences which must result, at no very distant period, to those misguided, stubborn, and short-sighted workmen who are the cause of the evil. In a trade where workmen are known to earn from 70l. to 901. per annum, paucity of wages is a bad plea. The object of these men is for an increase, and obviously also to form such laws or standing rules amongst themselves as will regulate the rate of labour, not only at their will, but also render it imperative upon all to employ the workmen belonging to their Union. This species of dictation cannot be submitted to tamely; the evil has driven myself and many others to the necessity of seeking a remedy elsewhere. Several vessels in which I am interested required rather extensive repairs, which, from the cause stated, I could not get effected here, and they have been sent to the North of Europe in this imperfect state at my own risk; and I have now the satisfaction of knowing that I shall there accomplish my repairs in an equally secure manner, and at a much less expense, in some cases for one-half, and in no instance for so much as two-thirds, of the cost of effecting such repairs here. In this way some thousands will be expended, and I confess it would be more gratifying to my feelings to expend this at home than in employing foreigners; but when they evince a proper feeling of re

spect to those who do employ them— when they work well, and also cheap, employing them is decidedly more satisfactory than giving way to insolence at home. The extent to which this remedy has been sought this year is considerable, and the effect of turning the stream of capital cannot be far remote; the extent to which this mode of relief will be sought, will be equally general, as is the desire of man to take care of his own interest. My object in writing this letter is to show the effect produced by an unnatural found that the wages of labour are cause; and as, on comparison, it is already by far too high in this country, abundance of employment will only eventually be secured, in a permanent shape, by a very serious reduction. Until that takes place, we when it is manifestly our interest to must continue to employ foreigners,

'do so.

ftt!

I am, Sir,

Your obedient servant,
A SHIPOWNEr.

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What is the mean proportional between 5 and 20?-Set 5 on C to 5 on D, then against 20 on C stands 10 on D, the mean proportional sought.

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What is the third proportional to 26 and 48?-Set 26 on B to 48 on

A, then against 48 on B is 89 on A, the third proportional.

EXAMPLE II.

Required the third proportional to 144 and 864-Set 144 on B to 864 on A, then against 864 on B is 5184, the third proportional on A, as required.

PROBLEM VII.

To find a fourth proportional to three given numbers, or, which is the same thing, to perform the operation of the Rule of Three.

RULE.

Set the first term on B to the second on A, then against the third term on B stands the fourth term, or number required on A.

EXAMPLE I.

What is the fourth proportional to 12, 18, and 36?-Set 12 on B to 18 on A, then against 36 on B is 54 on A, the fourth proportional required.

EXAMPLE II.

If 30 deals cost 94., what will 180 cost?-Set 30 on B to 9 on A, then against 180 on B stands 54 on A, which is 54/., the answer.

NOTE.

The foregoing Problems apply, it will be observed, to the use of the rule, as regards the working of abstract numbers; we will therefore proceed to its application to the purposes of mensuration, as regards artificers' work and the art of guaging.

PROBLEM VIII.

To find the area or superficial content in feet, &c. of any board or plank.

RULE.

Set 12 on B to the width, in inches, is the superficial content in feet and on A, and against the length on B tenth parts of feet on A.

EXAMPLE.

What is the superficial content of inches, and length 14 feet 4 inches? a board whose width is 2 feet 6 -Set 12 on B to 30 (as 30 inches equal 2 feet 6 inches) on A, then against 144 (as 4 inches is the third of a foot) on B stands 35 feet, and very near another foot, which we may estimate at 10 inches; the answer is therefore 35 feet 10 inches, which, if we try it by cross multiplication, we shall find correct.

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SIR,-In so commercial a country as England, it has often surprised me that no attempt has been made for effectually Mooring Ships in Roadsteads, as every heavy gale of wind is sure to be followed by an account of vessels driven from their anchors, on some part of the coast, too frequently accompanied by a melancholy catalogue of loss of life and property. The following plan is therefore submitted, with due deference, to the public, and if it should be the means of saving a single vessel from shipwreck, the object of the writer will be attained. The plan is very simple, and will at once be understood from the figure. It consists merely in securing a large buoy in such a manner to a block of cast iron, that it cannot possibly be

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METEOROLOGICAL JOURNAL FOR MAY.

A strong iron hoop passes round the centre of the buoy, to which the chain and ring are made fast, and the chain must be of sufficient length to allow the buoy to rise to the surface at high water.

The cast-iron block must be sunk into the bottom of the sea by means of the diving-bell, until the top of it is level with the ground; and if any additional security is required, piles may be driven round it.

It is conceived, that a buoy of these dimensions would be sufficient to hold a vessel of three or four hundred tons burden under any circumstances; but for large vessels the dimensions ought to be increased considerably, as that would enable them to ride much easier.

The principal cause of a vessel dragging her anchor, or parting her cable in a gale of wind, is the jerk that is produced by a heavy sea striking her when the cable is on the stretch. By the proposed plan this would be guarded against, as the tendency of the buoy to rise perpendicularly, while the ship pulled horizontally, would cause a spring on the cable, so as to prevent any sudden jerk.

A vessel moored in this manner would probably not require to veer out more than twenty or thirty fathoms of cable; and the best manner of bringing up would be, to make fast a hawser to the buoy, heave upon it until the latter came under the bows, then pass the cable (of iron) through the ring of the buoy, and bring the end on board; the cable would thus be double, and a vessel could get under weigh in an instant by letting go one end of it.

Buoys of this description might be laid down (in the Downs, for instance) in lines, at different distances from the shore; and a vessel, instead of looking out for good holding-ground, might bring up as near to the land as her draught of water would permit her, by which means her communication with it would be much facilitated. They might also be laid down in rocky ground, where ships cannot anchor at all; for when, by means of the diving-bell, rocks can be blasted under water with so

much facility, it is surely not unreasonable to suppose, that by the same means bolts might be fixed in them sufficient to hold any vessel. That the plan here submitted is feasible, may perhaps appear from the use of mooring chains in several of our harbours, which is very much analogous to it,

To submit any thing of the kind to the Government is generally up-hill work; but if this should happen to come under the notice of the Gentlemen at Lloyd's, perhaps they may think it worth a trial.

I am,

Sir,

Your obedient servant,
M

Dublin.

METEOROLOGICAL JOURNAL

FOR MAY, 1825.

BY DR, BURNEY,
Of Gosport Observatory.

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[To be continued Monthly. ]

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[We have to express our obligations to Dr. Burney, of Gosport, for his kind offer to enrich our pages with a regular report of his meteorological observations at Gosport. The one with which we commence will give our readers a good foretaste of the instruction and entertainment they may anticipate from the pen of this able and intelligent observer.-ED.]

The first part of this month was wet, and the latter part generally dry. Seve

ral sudden transitions have occurred in the temperature of the air, as is commonly the case in May; and slight frosts in the nights of the 13th, 14th, 27th, and 28th. Some of the days and nights have been 13 degrees colder than others, and the decrease in temperature becween the 24th and 28th was 30 degrees. The showers of rain and heavy dews after the hot sunshine have been found beneficial to the grass lands, the young wheats, and to vegetation in general. From the thunmodifications of clouds, produced by opdery state of the prevailing compound posing currents of air, several blight days have been experienced, which, with

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