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340 REMARKS ON MR. PALMER'S SUSPENSION RAILWAYS. carriage might be made as Dixon Val- ments of circles, will at first much lance proposes, except the shafts, which facilitate the draft, as we have just should be made as above.

stated, depends upon the well-known I am, Sir,

geometrical problem, that a circle Your very humble servant,

described within another circle can WILLIAM Downes,

only touch it in a point; therefore, as

long as these forms continue perfect, 111, Aldersgate-street.

the lateral friction of the projecting part of the rim of the wheel against the side of the rail will be avoided,

and so long will a great source of reREMARKS ON MR. PALMER'S SUS.

sistance, which is experienced in other PENSION RAILWAYS.

railroads, be overcome. (See Mech. Mag. page 287, vol. 111.)

The Penryn railway, which was ori

ginally formed in this manner, bad, Mr. Palmer asserts that his plan will

asserts that his plan will at first, all the advantages stated; cause a great saving in embankments, but, according to the authority of Mr. bridges, culverts, and drains, and that Benjamin Wyatt (for which see Rethe carriages will be moved on it with

pertory of Arts, second series, vol. 111. less friction and resistance than on the

page 285), the two circular surfaces of railways hitherto in use; averring that the rail, and of the wheel's rim, as a horse can draw a load on it, when they wore, excavated the latter so level, of 33,750 pounds two miles and

much, and caused it to fit so tight, as a half in an hour, which on the best to occasion much friction, and make it performing edge railway that he had

necessary to change the wheels so heard of (that near Newcastle-on- often, that another form of rail and Tyne), could move only 17,773 pounds wheel became necessary; from which at the same rate.

it follows, that time is needful in expeWe should be greatly at loss to ac- riments of this sort as much as any count for this superiority of perform- thing else, and that it is requisite new ance of Mr. Palmer's railway, and kinds of railways should be in perfect even to suspect exaggeration, could operation for a reasonable period before we not see, in the nice adjustment of their superiority can be allowed. Mr. Palmer's apparatus, and in his A railway of Mr. Palmer's construccurious contrivance to lessen the fric- tion has been erected at Cheshunt, tion of his wheels (which we are, by- near Waltham, to carry bricks from the-bye, inclined to attribute to its Mr. Gibbs's fields, about a mile, to the bringing a larger surface of the axle river Lea; it is constructed of wood, and hollow box of the nave into con- with posts about five feet high, and tact, instead of the oil being prevented ten feet apart, as we are informed, by it from assuming the shape of a and has the surface of the rail covered wedge, as Mr. Palmer asserts), some with an iron plate. Nothing, at prewhat to justify the validity of the ex- sent, can be learned from this expeperiment; to this we have to add, that riment, but that the plan is feasible, the shape of the surface of this rail, which we never doubted; but, for the which is the segment of a circle, and reasons stated, we must wait for the the hollow rim of the wheel being also effect of wear and of the weather upon of tbe same circular form, will at first it, before we can decide how far the give a great superiority to the perform- pósts will maintain their upright poance of the apparatus, which the power sition, and the rails their level, the of adiusting the level, or inclination of first of which points we do not think the rail by the wedges, to unusual sufficiently provided for by the patennicety, must greatly assist. But as all tee. In point of expense, a wooden these circumstances are equally appli• rail can be no guide for those to be cable to the common double railroads made of iron ; and when formed of of the edge form, we think that far- this latter material, we think the pather trials than those made previous to tentee deceives himself in supposiug the publication of his book will be that his railway can be made cheaper necessary, impartially conducted, with than a common double one ; for, sup. wheels, axles, and both parts of the posing his made with rails of the same apparatus, equally good and perfect in strength as they are, and of course rethe other species of railroads, before quiring supports, as they do, at every the question can be fairly decided three feet, or thereabouts, now his

That the form of the surface of the pillars being three feet at least above rail and rim of the wheels, being seg- ground, and as much more below the

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earth (according to his drawings), and though it will, when the centre of grarequiring to be of considerably greater vity of the load is placed below the substance, it is evident that they will rail, keep them from tumbling off take at least double the weight of irou directly, yet will not prevent the risk for their construction, which would be of the accident mentioned, while it will necessary for the second rail, saved by increase that of their being knocked his plan; and if, as he proposes, they against the posts.

In conclusion, were we obliged to gained in this respect, since the rails

decide on the question in the present then must be made so much stronger in proportion (to which must be added,

stage of this experiment, which, howthat they must in all cases be made of

ever, we do not wish to do, we would

say that the plan of single railways double the strength of common rails,

should be confined to that species of one of them having to sustain the load of two of these); and as for the lengths

them constructed at Cheshunt, as they of ten feet between the posts sug

would be much too costly if formed of

iron, for the reasons before stated, gested, their weight, to carry the usual loads, must be so much greater than

The great defect of the wooden fram

ing would be its want of durability, that of any now used, that we much doubt if any of them, of iron solely,

and the expense of its repairs, parti

cularly in the posts, which would be will ever be constructed.

extremely liable to rot at the level of That erecting numerous lofty pillars the ground; for which, in order to of iron, as proposed by the patentee, show that we have no ill will to the can cost less than embankments of plan, from being able to see its defects, earth (in general the cheapest mode we will point out a remedy which will known of raising an elevated surface), make them more durable and facilitate we cannot in any respect credit, and the repairs—which is, to have square can still less give faith to the advan- cast iron sockets, two or three feet tage of making railways of this kind long, placed so as to occupy this porten feet high above the level of the tion of them, let down firmly, for half earth, advocated by some of his friends. their length, on the lower part of the

We have further to remark. that posts, secured in the earth as before loads carried as designed on this rail

described, and the other half forming way will, from their pendulous ar

a receptacle for the bottom of the rangement, be extremely liable to be

upper portion, which should be formed knocked against the posts in high

so as to project a little beyond it at winds, to the great damage of the

every side, to throw off the rain; and goods carried, as well as to the obstruc

in order that the fitting between the

wood and the iron socket might be tion of their conveyance, which, in case of a storm, blowing across the

more perfectly tight, the wood in this rail, may be sometimes so great as to

part should be previously impressed render the railway totally impassable

by screws-a method already practised by

to great benefit in the preparation of for the time of its duration.

staves for casks; to facilitate which The injury from unequal loads at process we have advised the sockets to the two sides of the carriages, we do be made square instead of cylindricalnot think would be found so slight as a form which, in other respects, might asserted by the patentee, who states, at first appear more advisable. that all acquainted with geometry must be of his opinion on this point. Now,

Repertory of Patent Inventions. in the first place, it remains with him to show what problem of geometry can be brought to bear on the question, and that he has not used the word geo

SINGLE-WHEEL CLOCK. metry here in the vulgar sense of equi

SIR,-Having seen, in your valuable librium; and, in the next place, to point out how he prevents the danger

work (page 319, vol. 111.), an account incurred by the oblique position of the

of a clock with one wheel, by B. P. C. wheels, which this must occasion, of No. 10, Wolcot-place, Lambeth, I imthe carriage being entirely dismounted. mediately set to work, and made one The rods which connect the loads with

according to his direction; but when the axles, being jointed to them so as be at right angles to them in all their

finished, I was disappointed to find it oscillations (which, we suppose, is what did not answer. The clock, when is meant by their being inflexible), wound up, unwound itself in two

342

HYDROSTATICS-SINGULAR FACT. minutes : we could not, by any weight, in diverging lines ; but as the moprevent its rapid descent.

mentum of such minute particles is Length of the line............4 feet. very inconsiderable, this diverging Spindle................ 1 foot 1 inch. tendency is soon overcome by the Wheel diameter............4 inches.

mutual attraction of the particles,

and the stream thus gradually dimi. Tin barrel ................7 inches.

nishes in diameter until it reaches · I should feel very much obliged if the earth. Now, Mr. W. considers B. P. C., through the medium of your that the tube, when applied to the valuable publication, would give us aperture, draws, by its capillary atthe measurement of his clock.

traction, a portion of the stream toI am, Sir,

wards its internal upper surface, and Your obedient servant,

passes it along that surface until it A SUBSCRIBER AND JOURNEYMAN

reaches the extremity; peventing, CARPENTER.

by this means, the stream from asRoyston, July 15th, 1825.

suming its natural converging conical form, and producing a sort of vacuum in the stream, which the

water from the vessel immediately HYDROSTATICS--SINGULAR TACT.

rushes to supply. SIR, -Mr. N. Webster has re. This is the opinion of Mr. W. on cently, in several parts of Cornwall, the principle by which the effect, delivered courses of very useful lee- now under consideration, is protures on Experimental Philosophy. duced: but as it is not at all satisDuring the course which he delivered factory to me, I beg to submit an

lowing experiment :-A cylindrical of your scientific readers. vessel full of water was placed on the When the water issues from the table; through an aperture in the meie orifice, without any tube afside of it, a certain quantity of the fixed, as the lines of pressure towards fluid was discharged in 24 seconds. the aperture proceed from every diA straight tube was then attached to rection withiu the vessel, they must, the aperture, and the same quantity by acting against one anothr", diof water flowed through it in 21 se- minish considerably the effect of the conds; on the straight tube being aggregate pressure, and consequently exchanged for a diverging conical diminish also the quantity of water tube, the water passed in 18 seconds. discharged in a given period ; but

The cause of this effect, Mr. Web- when the tube is affixed, and the ster observed, has not yet been ex- 'water flows from the end of it, the plained by philosophers; and the whole pressure exists nearly in a manner in which that gentleman ac- line with the axis of the stream, and counts for it is the following :-It is therefore acts in the most advanwell known, that the figure described tageous manner to facilitate the disby a stream of water, issuing forci. charge of the fluid, without one part bly from an aperture in the side of a of the pressure impeding another vessel, is that of a converging cone; part. And if, from the cause I have and the reason why the diameter of just mentioned, there be any impethat part of the streain which is near diment to the free passage of the the orifice is greater than that of any water from the vessel into the tube, other part of the stream, is, I ima- and a vacuum should thereby exist gine, owing chiefly to the pressure in the tube, that vacuum would inwithin the vessel towards the orifice, stantly be supplied, by its affording operating not only in a line in the à greater facility to the passage of direction of the axis of the stream, the water through the orifice. Ano, but also in lines proceeding from ther circumstance which conduces to every direction in the interior of the the more rapid discharge of the vessel; thereby giving to the parti. water through the tube, than through cles of the fluid a tendency, on is- the mere orifice, is, I consider, the euing from the aperture, to By of pressure of the water in the vessel NEW APPLICATIONS OF THE LEVER POWER.

343 continuing to act on the stream after taken that the tube be not so wide as its passage through the orifice, by to allow the admission of air into it which continued pressure the stream whilst the water is flowing. acquires a progressive increase of Such are my ideas on this subject; velocity, until its discharge from the if they be erroneous, I shall feel inextremity of the tube. That more debted to any of your Correspondents water should flow in a given period who will correct them. through a diverging conical tube, than through a straight one, is, per

I am, Sir, haps, owing to the friction of the Your very humble servant, stream being less in the former than

P.E. in the latter; but care should be Redruth.

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SIR,—I send you herewith a sketch of two new applications of the power of the Lever : one to the working of a Milk Churn, and the other to the working of a Wheel with a double crank.

Description. Fig. 1st represents the milk churn, with two churn-staffs, wrought by the lever. The two charn-staffs descend and asceod alternately; there is a small fillet down the middle of the churn, on each side, to keep the churn-staffs from coming in contact. The churn is four feet six inches in height, nine

teen inches long and nine wide; the
cover, or lid, is in two pieces; the hole
for each churn-staff is surrounded with
a square hopper, to keep the milk froir
running over in the act of churning.
The small duts round the upper part
of the churn are air-holes.

Fig. 2nd is a lever applied to a wheel with a double crank.

I am, Sir,
Your most obedient servant,

. Dixon VALLANCE. Libberton, by Carnwath,

Lanarkshire,

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Sir,-The unsuccessful (but far idea was this to enable a body which from fruitless) search made to dis. would float in a heavy medium and cover the “ philosopher's stone,” sink in a lighter one, to pass succesand the “elixir vitæ,” were produc- sively through the one to the other, tive of most important and beneficial the continuation of which would be results in the kingdom of chemistry; the end in view. To say that valves so, by a parity of consequence, I am cannot be made to act as proposed, disposed to believe that, froin in- will not be to show the rationale (if I quiry after the “perpetual motion” may su say) upon which the idea is (though equally unsuccessful), a fallacious. similar good will result to the me. The fi

The figure is supposed to be tubuchanical world. After this apo- lar, and made of glass, for the purlogy for those who may sometimes

pose of seeing the action of the balls think (and myself amorigst the num

inside, which float or fall as they ber) upon this much ridiculed, and

travel from air through water, and now almost totally exploded, sub

from water through air. The foot iect. I beg leave to offer to your is supposed to be placed in water, notice, ånd for the momentary amuse

but it would answer the same purment, perhaps, of some of your

our pose if the bottom were closed. readers, the prefixed device. The Po point at which, like all the rest, it fails, I confess I did not (as I do now)

Description of the Engraving. plainly perceive at once,although cer- No. 1, the left leg, filled with water tainly it is very obvious, and will be, from B to A. no doubt (as I shall leave it to be), 2 and 3, valves, having in their cenimmediately pointed out by some of tres very small projecting valves—they your Correspondents. The original all open upwards.

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