JONES'S MINERS ASCENDING AND

DESCENDING MACHINE.

Sir,-Much of the time and attention of the good people of Cornwall, and elsewhere, has been directed toward the construction of a machine for abridging the arduous toil of the miner to going to and from his work; and which, owing to the great depth of many of the mines, can only be worked at great expense to the adventurers, and serious injury to the health of the miners.

A large working model, of which the annexed is a rough drawing, was exhibited at the last meeting of the Royal Cornwall Polytechnic Society, and was said by the judges, in letter which I received from them, to overcome four difficulties not met by any previous plans, and for which they awarded their first bronze medal.

B BC, are three stout rods of timber, with notches or gaps at every twelve feet; X is a strong piece of timber, in which the four iron catches H H H H work, and to which the car is attached.

JJ, are two upright pieces of wood, which, with the two handles J H, and cross pieces S S, which are for working the catches and governing the machine. AA, two balance bobs.

NN, are two strong pieces of timber tapering to one side, and shod with iron, and which can be thrown out in an instant by placing the foot upon the treadle K, which, by encountering the side catches must infallibly check any sudden descent; K depresses a strong elliptic spring.

To produce the motion, the middle rod C is made to alternate, up and down, by the mine engine, in strokes of 13 feet, that is, 6 inches each side of the points of suspension, insuring in the ascent a firmer hold, and in the descent, easing the catches required to be withdrawn. serves as a door when folded up, or for a foot-path for getting in and out at the different levels.

LL,

In making the ascent, the engine does all the work, nothing more being necessary, on the part of the persons in the car, than to put forth the middle catches when the order to start is given.

The descent is effected in the following manner in every stroke of the rod, whether up or down, two sets of niches pass the middle catches, observing in the descent you drop the middle catches into the last niches upon the up-stroke,

and immediately withdrawthe side catches, when the car will be suspended from the middle rod, and follow it in its descent. Any negligence upon the part.of the guide, will be productive of no harm, but will take the car a stroke higher, and give him the trouble of doing his work over again.

It is calculated that it might be worked in its ascent, as the engine does all the work with great ease at six strokes per minute, and at 12 feet per stroke, or 216 fathoms in 18 minutes.

Yours most respectfully,

WM. JONES.

ON THE DANGERS OF FIRE FROM LOCOMOTIVE AND MARINE FURNACE FLUES.

Sir, Considerable discussion has at different times taken place, as to the probable extent of danger, in the shape of accidental conflagrations likely to arise from the sparks of railway locomotives. Experience has shown that the actual amount of danger has, in general, been greatly overrated, although accidents of this kind have been rather numerous, and in some cases sufficiently costly, (the late case of the Manchester mail-bag for instance) to render every expedient desirable by which the liability of accidents may be decreased. A good deal of care has been bestowed upon this subject, and your 26th volume contains a report of the Lords' Committee, on the danger by fire likely to arise from locomotive engines passing through narrow streets, with extracts from the evidence; but with respect to steam-boats, which would seem to be in many respects more dangerous, very little caution seems to obtain. I have several times witnessed, what I am given to understand is a frequent occurrence, the soot in the funnel in a state of intense combustion, pouring forth showers of sparks on the deck, and all around. Returning over London bridge, one night in particular, I saw a large steam-boat (from Gravesend I believe) lying at Nicholson's Wharf, the chimney of which was belching_forth fire, both "fast and furious." Large flakes of ignited soot were falling thickly on the deck and rigging of this and some adjacent vessels, and part were carried on to the wharf; the settlement of these particles on dry combustible matter would seem likely enough to occasion a tre

mendous conflagration-such as usually occurs in places of this character, when once fired.

By advices recently received from New York, we learn there has been a most destructive fire in the city of Hudson, sixty houses are reported to have been consumed, and the property destroyed is valued at upwards of two hundred thousand pounds. This catastrophe is said to have been originated by a spark from the steam-boat Congress," which was at the time lying in the dock.

66

The practice of burning out the flues, though a common, is decidedly a bad one; some other method of cleansing should be employed, and in the event of the soot taking fire, instantaneous methods of extinction should be resorted to. The introduction of a small jet of water, or a cartridge, within the funnel, would soon remove all chance of mischief.

The small number of cases in which any serious consequences arise from the foregoing causes may induce a sort of apathy in those who are frequent observers, that may in some cases lead to serious loss. The foregoing narrative shows what has happened, and may happen again, and should be a sufficient warning to persons in charge of steam-boats lying in tiers of shipping, in docks, or at wharfs, to be careful of flying sparks. I remain, Sir, yours respectfully, WM. BADDELEY.

London, Sept. 8, 1838.

66 EXCELLENT FIRE-ESCAPE."

"Patriæ sis idoneus."

Sir,-In that highly respectable paper the Sunday Times of August 26th, is a paragraph under the above title, abridged from a letter by myself. I should be very glad, on public grounds, to give it additional extension. The subject may interest every one of us at some period or other,and has, like the "steam explosions," derived a more painful and pressing interest, from frequent recent accidents; to an instance of which, involving four deaths in the street where this is dated, in November, 1835, is owing the existence of the numerous fire-escapes now kept in different parts of London.

The fire-escape which I first saw and tried in the year 1818,-the only one of the kind I ever saw, and the owner could

not tell the name of the inventor, and whether it had been ever patented,-was in the form of a pipe or trough, with sticks on the upper surface like a ladder, or like the heavy wooden trough moveable on wheels, lately invented,* and probably pirated, from it; differing, however, essentially in being constructed of canvass, and of course both flexible and portable; rolling up, to the best of my recollection, in a circle of 2 or 3 feet diameter, about the circumference of a fore coach-wheel. I believe it fastened at the top by grappling-hooks, but it has since been suggested to me that a transverse bar of iron wire, having a purchase against the inner side of the window, would be more sure. Of course this escape is let down from a window, &c., and the party to be rescued gets in at the top and slides down. Down indeed he must go when he has entered, no misgiving, or drawing-back, can prevent his being saved; but if the rapid transit has a breathless and unpleasant effect, he can moderate and regulate it, by laying hold of the successive sticks above him.

I have heard it remarked by an eminent mathematician, and popular London clergyman, that "all fire-escapes which presuppose much dexterity and presence of mind in the parties who are to be rescued, have a strong chance of failure." This I believe; but the security of this is so self-evident, and may be so carefully and leisurely considered before-hand, that there is as little scope for nervousness as in anything of the kind hitherto broached.

The weight, I should imagine, for a length of 60 feet would not at the utmost exceed 30lbs., and the cost might be between 3 and £4. In almost every respect, therefore, I think it preferable to the wooden trough. It is impossible for the latter to be used "within" a house, or to be used without much communication and probable delay from external power; and when the canvass one is adapted for being raised from without (of which I am going to speak) it will have about the same advantage in portability and celerity that a "watering-pot" would have over a "butt."

This 66 Escape," which I saw at Woburn, in Bedfordshire, where it be

*If our correspondent refers to Wivell's fire escape, he is mistaken; the trough is of canvass. See Mech, Mag, No. 723,-ED. M. M..

longed to a celebrated poet, a native of that place, and librarian to the Duke of Bedford, Mr. Wiffen, may have been formerly better known, and may be now known to many, but I am convinced it is not generally so; whilst, therefore, it may be laudable to extend its notice, it would be culpable not to do so.

After anxious consideration and some experience, I have proposed the following three improvements.-1st. That it should be periodically washed with a solution of potass and other ingredients (which some of your readers can specify) to enable it to withstand the flames. 2nd. That in case persons should not be at hand to receive and firm it below, a weight (attached to the lower end by a short cord) should be thrown out with it to steady it, at a sufficient distance from the wall; probably from cwt. upwards, would be sufficient for this purpose. 3rd. That as he would be no friend to his species who should recommend the neglect of external means, this escape might be raised from without, by means of a rod in pieces, jointed after the manner of a fishing-rod, the lower pieces of course longer than the upper ones, and of a length corresponding to the escape-from 50 to 70 feet, many houses requiring such a height to their summits. Whether, if there was awkwardness in fixing it at the top, this rod would bear the weight of a person descending without bending or snapping, I doubt, though I think it possible; however, a pole might be often at hand to be substituted.

Of

course any one might ascend by this escape when fixed, with as much ease as by a ladder. The weight of the rod I have estimated at 18 lbs.; and I suppose there may be woods even better than larch for the purpose.

Commending this necessarily long statement to kind and judicious public consideration,

I am, Sir, yours respectfully,
J. D. PARRY.
Tottenham Court Road, September 4, 1838.

P.S. Would it be possible to construct a portable staircase with wire railings and a "landing" of 2 feet square, not exceeding 3 or 4 cwt., and nearly as easy of transfer, on wheels, as the wooden trough, being, of course, much lighter than an engine?-If so, there might be cases of infirmity, &c., where it would be invaluable.

LOCOMOTION BY ROCKETS-COUP DE DE GRACE ROCKET.

Sir, General Andreosi, who has written the best works extant on practical artillery, &c. did many years ago suggest the use of large rockets for propelling a boat loaded with shells, gunpowder, &c., along the water, against the sides of an enemy's ship. In 1825, Colonel Paixbaus rementions the subject, and in 1824, Colonel Ravichio, in the French service (engineers), promulgated the same idea. In 1824 I constructed a kind of little boat, which inclosed a large shell rocket (32 lbs.) which floats on the water, and being fired by a particular contrivance of my own, the boat-like envelope is blown to pieces, and the rocket skims along, or close to the surface of the water, good fifteen hundred yards, so as to enter the enemy's ship between wind and water. My method of giving them the proper direction is simple, easy, and exact, and may be effected from an open boat. I could construct rockets of one hundred to five hundred pounds weight each, which, containing from thirty to two hundred pounds of powder in their cast-iron conical heads, for explosion in a ship's sides, may merit the mame of coup de grace rockets. They may be allowed to remain on the water, washed over by the waves, for hours, or days, without injury, or any chance of missing fire. One of my shot-proof steam ships provided with a few such rockets, armed with a twelve-inch bomb-cannon for horizontal projection, and a frame for throwing fifty of my prehensile incendiary rockets into the sails and rigging of a ship, such as I proposed to the Lord High Admiral of England in 1828, will constitute a formidable antagonist to any ship of war, if manœvered in the proper way, at a proper distance. I am, &c.,

F. MACERONI.

WOODEN PAVING-HINTS ON ROAD MAKING.

Sir,-You see, how the paving people are going on with their layers of loose gravel, then loose broken granite-then new large stones,-then ramming with their absurd hand rammer,-then liquid mortar,-then a corfortable cover of sand and rubbish. And then-after a few

weeks-holes and bumps as bad as everand then anon-the whole job to do over again! Glory be to the paving boards, and to the vestry boards that can invent so much capital work for paving-men, and granite-mongers-and for the wielders of the "Lady Griffins" who grunt in vain to give the stones and the subjacent mass compression enough to stand the shock of even a Tilbury's wheel! Pray, Mr. Editor, do remind the people who have to pay for such vagaries, that from the pages of your valuable periodical for 1825,-they will learn how to form a carriage pavement that shall be as level as a billiard table, and remain so under any pressure from carriages, as long as the stones shall last, becoming better and better, the longer it is used-and any part of it being taking up for pipe laying, immediately restored to uniformity of hardness with the rest. Moreover, that all these advantages may be secured-with the old small stones, and without any application of the gravel, broken granite, and mortar, so expensively and absurdly applied by the present paviours. I would again befriend the public, by calling their attention to your observations on my Hints to Paviors (2nd edition, 1833), a copy of which I sent to the members of the Oxford-street Committee. By the bye the Monthly Repository for February or January 1834, ridicules my suggestion of paving certain streets, and the vicinity of churches, with blocks of wood; and portrays the citizens of St. Giles's holding out their dusky hands before a good Christmas fire, furnished from the carriage way; he puts into their mouths a song of praise to me, of which the following is a fragment:

"London streets are paved with wood,
Long live Maceroni;

For we'll blow out with summut good, Saved out on our coal money." I trust that the Repository will indite a new song to his old tune, in honour of the wooden paviours who are now about to gladden the hearts and warm the bodies of the St. Giles's songsters. Seriously speaking, Sir, it is infamous that the public should be duped and robbed for so many years, by the jobbers in a most expensive, silly, inefficient mode of paving this great metropolis, when the only method which can suit all the con

tingences and features of the case, is of fered them at less than half of the expense. It may be as well for me, with your permission, just to state the main principle of my paving plan:-First, the earth is levelled and then hardened by a machine consisting of a frame on wheels, supporting a block that weighs 3 or 500 pounds, worked like a minor pile-driving monkey; the stones are then laid, and beaten down by the broad flat head of the stone driver. After a short time, if any inequalities of surface appear, the protuberances are beaten down,-and these can be distinguished with great accuracy by pouring water over the surface. Thus, the pavement must become better and better, and if any part is taken up, that part can be immediately reduced to any degree of solidity by the machine. The stones that were used some years ago were much smaller than the new ones lately introduced to complete the paving job, and the smaller the stones, the better the pavement. Amongst other advantages, they do not become roundheaded. The stones should be squareended of equal sizes. Mortar is ridiculous, unless it be used as at Rome and Naples, especially at the former place, where the pavement is a thick horizontal wall, the small deep parallopepoidal stones being built in, and supported by, above a foot thick of the best puzzolana mortar. But, as I have shown in my Hints to Paviors, such a pavement will not do for London, where it has to be frequently disturbed, for sewers, pipes, &c. Of course the substratum would be improved by an admixture of brick and mortar rubbish, with a little chalk-but the earth and gravel already under it, is much disposed to harden by the formation of carburet of iron, and with my due me. chanical compression, will produce a far better, and quite durable level, which all the fuss and expense of the new-fangled jobbers will not secure for a week. Without the application of my means the wooden pavement will speedily become as uneven as the stone.

Inviting those whom it may concern to wipe the dust off the copies of Hints to Paviors that I have sent them, I remain, Sir,

Your obedient servant,
F. MACERONI.

Sept. 11, 1838.

ness, and comfortable appearance of the marble, without going to the expense of £4. 4s., and upwards.

I propose lining the top and sides with earthenware, which can be accomplished with ease, combining a neat appearance with a low price. If the slab in which the circle for the basin is made (and which I shall call the slab to distinguish it from the back and sides) be considered too large to be made conveniently in one piece, it can be made in two pieces, thus:

о

Ο

The ends A B being made with a shoulder, the ends CD made to correspond, will wrap over, and if bedded in plaster of Paris, the joint will be made impervious to water.

These slabs should be screwed on to the deal top with neat brass-headed screws, the holes in the slabs being, of course, countersunk to receive them. The back can, in like manner, be made in two pieces, as A; the sides B can be easily made in one piece; the crevices between the back, sides, and slabs should be pointed with plaster of Paris, or any other cement, as it is important that no wet should find its way between the earthenware and wood, as in that case the wood would rapidly decay. The back and sides should be made with a turnover edge, as may be seen at C, which is

B

a perpendicular section of B.

The shoulders of the slabs and backs, which wrap over, should not be glazed, in order that the cement may take a firm hold.

The stands, if fitted with earthenware in this manner, may be made of fir, and neatly painted in the usual manner, there is no fear that the stand will grow shabby, as the paint will in no part be subject to any rough wear and tear. If a little channel be made to run round the edge of the slab, communicating with a hole in the corner E, and from which an earthenware tube one inch long be continued downwards, all the slop will run off into a mug placed under it upon a little shelf.

I am, Sir, your humble servant,

Mile End.

E. R.