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PERPETUAL MOTION. admit of its being perpetually dis- heights in the legs of an inverted placed for the temporary purposes syphon, proved fatal to the scheme above mentioned. Morever, where of “ Philo-Montis.” I certainly are we to get a sufficient quantity consider the idea of gaining a perof such a Puzzolano mortar as is petual motion, by the passing of employed in Italy, with which the bodies through mediums of differpavement becomes as one rock? ent densities, is a very ingenious
With regard to the pavements, one, as it is the same in effect as if or, as I have ventured to call them, the specifie gravity of the moving the stone railways of Florence, Si. bodies was a variable quantity, enna, Milan, &c. &c. the objections which agrees very well with the to their adaptation to the streets definition of De La Hire, viz. “ to of London must also be obvious find a body heavier and lighter than enough. Independently of the enor- itself.” But it strikes me very mous expense of such materials, forcibly, that there is a better plan such a system could never answer of applying tbis principle than the in streets where vehicles of all de- one described by P. M. Let aa scriptions, going at every degree endless chain or rope be passed of velocity, have occasion to cross, over a pulley, and through a hole of pass, and run abreast of each other, similar diameter made in the botover the entire breadth of the street. tom of a vessel filled with water, Such large stones, whether of gra. so that one-half of the rope will alnite or limestone, would soon be- ways be in the water, and the other come dangerously smooth, their half in air; now let this chain or longitudinal edges would wear, rope be divided into equal links or and ruts proportionally be formed divisions, each constructed in the along them. ,
following manner :-Let pieces of cork, or any other light substance,
be attached to the rope, exactly in PERPETUAL MOTION,
the same manner as the whaleSIR,_From the ingenuity dis bones are fastened to the stick of played by “ Pbilo-Montis," in his an umbrella, so that they may contrivance to effect a Perpetual form a complete cylinder, when Motion, I am led to consider him passing through the hole in the to be a young man of very pro- bottom of the vessel, and prevent mising abilities : and I have no the water from rushing out; but doubt, when he hit upon the idea the moment one of these links gets which he has so well described, be through the hole (which will be imthought he had acbieved one of mediately filled by another), these the greatest discoveries of the age. pieces of cork will radiate, or fiy However, it happens, most unfor-' out, like the spokes of a wheel, tunately for speculators of this cast, and exert a force, proportionate to that when the pleasing reveries and their lightness, to ascend to the feeling of self-complacency, always top of the vessel, and thus give attendant upon great success, have motion to the machine. subsided, and left the mind to cool I cannot let this opportunity slip, reflection, it is invariably found without reminding you of the pro. that some law of nature, some pro- mise made in your 58th Number, perty of matter which had before to favour your readers with some escaped notice, steps in, and, at illustrations of the Marquis of Worone fell swoop, the superstructure cester's Century of Inventions ; on whose battlements the projector a production, the value of which is had planted his fondest hopes, and every day rendered more manifest claims to immortality, vanishes, as by contrivances, of which he has if by magic, and “ leaves not a given the “ names and scantlings,” wreck behind.” In the present instance, the unfortunate property of water, or other fluids, to rise to
* The covtinuation of them has been
unavoidably deferred, but will shortly their own level, or stand at equal be resumed. -EDIT.
391 being announced to us week after your readers to know my method, week. Even the invention of G. M., which, with your leave, I shall given in your last Number, is a shortly lay before them. copy from No. 19 in the Marquis's
I am, Sir, yours, &c. , Collection; and I have no doubt
T. BELL. but that, in course of time, those Commercial-road, Whitechapel. inventions, which appear at first sight to be impossible, will not only be found practicable, but extremely STEAM CARRIAGES. simple in principle: for instance,. We took notice in a former Number No. 21 would be set down as chi. (p. 90, vol. iv.) of different attempts merical, bad we not a description that were making on the Continent, of the apparatus given in all our and in America, to apply Steam to the modern Encyclopædias, under the propelling of Carriages on land; and name of the “Gaining and Losing
we have now to add an account of an Buckets.” Although it is niy opi
invention of this sort in our own condnion that the Century of Inventions
try. It is copied from the Scotsman.'
" The constructor, Mr. Burstall, has been the means of forming is an Englishınan,' and, we bemapy a mechanical mind, by cre- lieve, an engineer by profession. We ating a spirit of inquiry after those found bim very communicative, and, sabjects, yet I also believe it has as far as we could judge from a short fallen into the hands of few persons conversation, well informed, not only who have not, from that time, be in the mechanical details of the steamcome determined perpetual-mo
engine and wheel carriage, but in the tionists; for if we can place any re
principles involved in their construcliance upon the Invention No. 56,
tion and motion. The Steam Carriage which seems so well attested, the
now preparing runs on four wheels,
and the propelling machinery is so Marquis was undoubtedly in the se- disposed as to make but an inconsicret. The plan which most people derable addition to the bulk of the adopt, who would accomplish the vehicle. The coach is to be of the point by means of weights, is, I dare ordinary description, with seats for the say,familiar to most of your readers, usual number of inside and outside viż. by means of falling levers,' a passengers. The distance between the description of which may be seen in
wheels across is the same as in comthe “ Mathematical Recreations,"
mon coaches; but the length of the translated by the late Dr. Hutton;
perch, or the distance between the fore
and hind wheels, is one foot greater. but, as the Doctor observes, “it The parts are disposed in the following may be easily shown that there is
order:-At the binder end, behipd the one position of the wheel in which
axle,and exactly under where the guard's the system is in equilibrium, and seat is in our common coaches, is the consequently will stop ;' the plan boiler, which is a cube of strong may therefore be given up as un
malleable plate iron, about three feet tangible. I have seen and read of
loog, three feet broad, and two feet many attempts to overcome this
deep. From this cube à neck about
eighteen inches long extends backobstacle by means of springs, &c.
ward, containing the grate, into which but they have been attended with
the coals are dropped gradually from a po better success. I am, however,
hopper by machinery. The upper surin possession of a method of con
face of the boiler is nearly on a level structing the machine, so that “all with the hinder axle, immediately the weights on the descending side behind which the flue or chimney, of the wheel shall be perpetually which is about nine inches diameter further from the centre than those
and seven or eight feet high, stands up, on the mounting side,” by which
its top being pretty nearly where the
guard's head is in a stage-coach. Bearrangements there seems to be an
tween the fore and hind wheels and equilibrium in EVERY position of
under the perch is a shallow square the wheel; and as I consider it to
copper box or cistern, which will conbe the nearest approach to, if not tain about 12 cubic feet or 90 gallons the identical construction of the of water. There are two steam-cylinMarquis, it may be agreeable to ders, of severr inches diameter, and 392
STEAM CARRIAGES. 12 inches stroke, which are placed in the opinion of the engineer, add about a foot before the hind axle. The about a ton and a half ; so that the, two beans, about three feet long, ex- Steam Coach, if loaded with twenty tend backward across the hind axle, persons and luggage, would not weighi and they move on a joint or fixed point more than three tons and a half; every at the back end, so that the lifting rod twenty miles the supply of water and wbich passes down to a crank on the coals will be required to be renewed, axle will make a stroke of about nine but this can be easily done in two or inches. The cylinders, beams, and three minutes. other working gear, are all above the “The engine, as in all the English locolevel of the axle, and will exactly oc- motive machines,is on the high pressure cupy a boot of the carriage, which, in principle. Its power is, of course, variathis case, will be merely a cover for ble; but, with a free pressure of 15 lbs. this part of the machinery. The boiler, it would be of three computed horses the cistern, and steam-cylinders, are power, which would be equal to the so placed as to balance one another on efficient for one of seven or eight the opposite sides of the axle of the horses, running at eight miles an hour. bind or large wheel, which will thus This will, probably, be sufficient to very properly sustain two-thirds of the give the Steam Coach the usual velocity weight. The carriage for the passen of stage-coaches. But where the supgers is placed between the hind and ply of fuel and water constitutes so fore wheels, but somewhat uearer the considerable a part of the burden of latter than is usual. Over the axle of the the vehicle, economy in the use of fore-wheels, but rather in a lower posi- these articles is of the first importance. tion than the driver usuallyoccupies, sits Accordingly, it forms part of the engithe director or steerer, who, by means neer's plan to let more or less water of a teethed circular rack aud a pinion, into the boiler, as a greater or less turns the axle of the fore-wheels to the force may be required. In going down right or left, and thus guides the a declivity, for instance, the steam will motion of the vehicle. The machine be entirely saved, and in going up an is nearly completed, and will be brought extra quantity will be used. The large to trial in a few days.
wheels, we think, are about four feet “Those who have followed us will now and a half in diameter, or fourteen in baye a tolerably accurate idea of this circumference. Supposing the engine Steam Carriage. It is a stage-coach, to make fifty double strokes per minute, with the machinery of a small double this would give the machine a velocity steam-engine stowed behind and below of eight miles an hour. If the expeit-the water cistern being under the riment succeed, the expense of fuel and body of the coach, the cylinders and attendance for an engine like this will beams in the boot, and the boiler sus- be such a mere trifle,compared with the pended behind the axle. A working keep of sixteen horses, that the cost rod passing down from the beam to a of travelling per coach to Glasgow, crank on the axle turns the hind which is now about fourpence per mile, wheels, which, in consequence of the may certainly be reduced two-thirds. great weight upon them, take a firm “Manydifficulties arise from the nature hold of the ground, and roll the man of the vehicle that have no existence in chine forward. The fore-wheels, which the steam-boat, and for which the artist are small, as in the common coach, bas provided very ingeniously. As the roll without any application of steamwheels, for instance, move unequally power. Thiuking, however, that in in turning, and may sometimes be resteep acclivities, the friction of both quired to move backward, they are fore and hind wheels might be wanted, connected with the axle by a sort of Mr. Burstall has contrived machinery bush with ratchet-work. Some of the for transmitting the motion of the hind pipes are twisted into a spiral, to give wheels to the fore ones, which can be them the elasticity necessary to withapplied at any time, and plays idly stand the shocks occasioned by the when not needed. Our conviction is, jolting motion of the wheels on rough that this part of the machinery will be roads. He observed, however, that as found unnecessary, and, as it adds to to steain-carriages moving on common the expense, friction, and weight, would roads, we have nothing but theory to have been better wanted.
guide us, and that experience will dis“ The commou stage-coach weighs cover defects which no skill can antiabout a ton. The machinery in this cipate. The observation is just, and vehicle, with the charge of water and we were well pleased to find that a coals (for a run of twenty miles) will, scheme so difficult was in the hands of WATCH-GLASS MICROSCOPE.
a person whose views were so judicious, riage, rests on springs, and that proand bis mechanical resources so consi- vision has been made for stopping or derable. There are a number of con- retarding the motion of the machine trivances, some of them very inge- by an invention (not new), the technious, of a secondary nature, which we nical name of which we do not know, have not alluded tö. But in looking but which we would call a friction hoop, back over our account, we find we have clasping the rim of a wheel. It opeomitted to mention that the whole ap- rates very effectually." paratus, as well as the body of the car
Sir,-Some years ago, I joined For the purpose of holding objects two small Watch-Glasses, of the to be examined, I place a brass pin, same diameter, in a bason of water, turning on a hinge, in the manner by pressing their edges together with represented, on one side of the frame, my finger and thumb, so as to fill and a forceps, with screw, on the them completely. When taken out, other, both of such a length as to set I was then in possession of a single exactly to the focus of the lens. microscope, whose focal length being There is a groove on each side of the 3-16ths of the distance of distinct frame to receive the pin and forceps vision, inagnified the surface of an when not used. One principal obobject 25 times. It then occurred ject ought to be, to make the frame to me, that two such glasses ce- sufficiently thick to protect the conmented together, leaving a small vexity of the glass-a small shagreen aperture to fill them up with pure case would secure the whole. spirit, and cased in a small frame şimilar to the drawing, would form an
I am, Sir, instrument simple in construction,
Yours respectfully, and excellent as a pocket companion, for the examination of minute ob
Thos. Henry Bell, jeets, such as plants, insects, &c. ... Alnwick.
From a Return of the Work performed by Fifty-nine Steam-Engines employed in the Cornish Mines, for July, 1825, it appears that six of them accomplished as follows :
IPounds listed one foot Engine and diameter of the high, by consuming Names of the Mines.
a bushel of coal.
ADVANTAGE OF THE DOUBLE Let us proceed, and suppose, withCYLINDER STEAM-ENGINE. out entering into minute detail, that
we have a single (or double) engine
on Woolf's principle, the relative [We have already inserted, p. 295,
capacities of the cylinders being as vol. iv., an answer to the inquiry on
I to 5 (which cylinders we will dethis subject; we select from several
signate by a and b); we raise the other answers the two following,
steam in the boiler to the pressure which furnish some useful explana
of 50lb. per square inch; let us tions.-Edit.]
blow through, and then apply it to
the top of a, whilst, at the same Sir, -Having observed a letter in time, the valves at the bottom of a, a late Number of your Publication, and top of b, are opened; the steam requiring information relative to the which was below the piston of a advantage of applying Steam on rushes intu the space above the pisWoolf's principle, and calling on ton of b, and expanding itself into any of “ the first engineers” for as- five times the space it previously ocsistance, allow me, through the same cupied, is, of course, reduced to medium, to attempt a reply. Al. 10lb. per square inch, which acts though I by no means lay claim to with equal force on the top of b and the above rank, “ mine being the bottom of a; therefore the effective last of all the families of Benjamin, force of the steam on the pistons and I the youngest in my father's may be stated at 50 - 101b = 40lb. house,” I contemplate little difficulty on U, and 10lb. on b, by which it is in convincing our friend F. J-k-n, very evident, that a great addition of that an absolute advantage is derived power is derived from raising steam by such application, which may be to a high temperature in the boiler, clearly demonstrated by practice or and employing it in that state before theory, mechanics or mathematics. reducing it to a common pressure.