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J. T. JEPPREE'S PATENT IMPROVEMENTS IN LIFTING AND PORCING WATER.

[Patent dated 11th January, 1842. Specification enrolled 11th June, 1842.] The improvements which form the three pairs of apertures, the pair leading to subject of this patent are remarkable for the barrel, (a and b,) the pair leading to the the union which they exhibit of great

discharge-pipes, (b and d,) and the pair ingenuity of contrivance, with extraordi leading to the well, or other source of supnary simplicity in the working results.

ply, (c and e,) will be open, and the other The chief improvement consists in dis

shut. The piston being now raised or drawn pensing, in lifting-pumps, with the move

out, the vacuum produced causes the water able valves in common use, and avoiding

to flow up from the well, or other source of

supply, through the aperture e, in the face thereby the great liability to derangement

of the piece 1, into the aperture e, in the to which such valves are necessarily sub face of the piece 5, whence it passes through ject. Mr. Jeffree's plan for this purpose the aperture f, fig. 1, into the barrel of the presents an obvious analogy to the sliding pump; by the return stroke of the piston, valve system adopted of late years in the water which was raised by the preceding steam-engines; but differs very much stroke is expelled from the pump-barrel, from it in its details.

through the apertures f and d, into the up

ward discharge-pipe connected with the " To the side of the barrel of the pump, opening d; while, at the same time, the vahe affixes a plain-surfaced piece of wood or cuum produced behind the piston causes the iron, of an oblong form, as represented by fig. water to flow up from the well, or other 1, in the accompanying engravings, having six source of supply, and pass through the aperrectangular apertures in it, a, b, c, d, e, f, tures b and a into the barrel, ready to be communicating with different passages made discharged at the next up or outward stroke through the body of the said piece, and repre of the piston. At every subsequent stroke sented in the sectional views, figs, 2, 3, and 4. of the piston there will, of course, be always The apertures a and f communicate with one body of water supplied to the pumppassages which lead into the barrel of the barrel, and one discharged from it, and that pump, one on each side of the piston, as alternately, at opposite ends of the piston; shown in the horizontal section, fig. 2; the and if the discharge-pipes connected with openings b and d lead upwards to the dis the openings b and d, are made to empty charge-pipes, as shown in the vertical sec themselves into one common mouth-piece, tion, fig. 3 ; while the apertures c and e lead the water will be discharged in one continu. downward to the well, or other source of

ous stream." supply, as represented in the sectional view, fig. 4, (the discharge and supply pipes being

A pump of this sort is obviously liable omitted in the engravings, as unnecessary to

to no other derangement than what may a clear comprehension of the invention.) To

occasionally arise from some of the aperthe plain-surfaced piece fig. 1 is adapted an

tures being obstructed ; but in that case other plain-surfaced piece, fig. 5, (the two

the evil can be at once got at, by simply pieces being ground true, to fit

each other ex taking off the upper piece, fig. 5, and actly,) and having six rectangular apertures,

when the obstruction is removed, the a,6%, c, da, e", and f?, leading to passages in pump becomes as good as ever. the said piece 5, which communicate with each For water-closets on board ships, the other in the manner shown in the horizontal patentee considers this pump to be parsection, fig. 6. To the outside of this piece, ticularly well adapted ; since it requires 5, is attached a rod, g, as shown in tig. 6, no supply cistern, the space required for which rod is parallel to the piston-rod, and which is often an insuperable objection moved to and fro simultaneously with it, and to the use of these conveniences at sea. by the same power, whatever that may be.

Another plan of construction, more The better to preserve the parallelism of the piece 5, it may be made to slide within

nearly resembling the slide-valve used flanges raised on the face of the piece l;

in steam-engines, and which might, in but when the pump is short, this is not

fact, be advantageously substituted for it thought to be necessary.

in many instances, as it would do entirely The action of the pump is as follows.

with the ordinary jacket and stuffing-box, Suppose the piston is at the bottom, or

is shown in fig, 7 and 8. farther end of the barrel, the two pieces 1 Fig. 7 shows the pump as it would be, and 5 will then be face to face, or in full if fitted with a slide-valve of the ordinary contact, and the apertures and solid parts of construction; and fig. 8 shows the sort the two faces will be in such relative posi of valve which the patentee proposes to tions to one another, that one of each of the substitute for it. In a pump of the

exactly to the barrel of the pump.

In Fig. 6.

the centre of the face there is a recess, c, of sufficient width to cover the two passages a and B, and behind it there is a

curved channel, d, cut out in the body a? 62 c d e f ?

of the slide, lengthwise, and terminating

at top and bottom in apertures in the face construction of fig. 7, the water rising in of the slide, which, as the slide is moved the pipe A flows by a curved passage

up and down, (by parallel connectors carried round the barrel of the pump to

with the piston-rod, in the usual manthe opening B, whence it passes upwards, ner,) communicate alternately with the through a channel, a, left open by the passages a and b, allowing the water to slide, into the barrel ; whilst, at the

How through c a, up into the pumpsame time, the water supposed to be left barrel, and through bd into the disin the lower part of the barrel by the charge-pipe e.

preceding stroke is forced up the passage b,

The patentee describes, also, a forcingand into the casing of the slide, whence pump, and a double-acting pump, with it is discharged through the orifice C. iwo concentric barrels, both very clever, The improved slide-valve, represented and apparently most efficient machines ; in fig. 8, is all in one piece, and of an

but a description of these we must reoblong form, with a plain face, but serve for some future Number. curved a little if necessary, so as to fit

MR. BOOTH'S NEW SYSTEM OF PROPELLING.* Sir, I have read a pamphlet entitled theory; but, “ demurring entirely" to “The Theory and Practice of Propelling it, he proceeds to state the ground of his through Water, &c. &c. by Henry Booth, objection. Liverpool,” and after giving it an atten Mr. Seaward gives in a tabular form tive consideration, I have thought some the result of his own investigations as a brief remarks may not be inadmissible practical man into the actual working of into your valuable journal.

steam vessels, deducing from observation The writer commences by stating fairly and experience the quantum of mechaenough, “ the theory of the comparative nical power required to move vessels of resistance of water at different velocities a given tonnage through the water at propounded by various writers on mecha different degrees of velocity. A few ex. nics in the last quarter of a century, and tracts from Mr. Seaward's table are recognised by engineers and men of quoted. The stated burthen of the vesscience in the present day." He states sel is supposed to consist both of engines correctly the purport of Mr. Seaward's and cargo, and to be kept equal and essay, which shows from facts and ex

uniform by diminishing the weight of perience the enormous cost at which a

cargo as you increase the weight of the smali increase in speed is accomplished, engines. a result which is in accordance with that “ With a vessel of 1200 tons so regulated 30 horse power will give 4 miles.

+ 112
250

10
" With a vessel of 955 tons 30 horses will give 5 miles an hour

240

103 “ With” one of 9ỉo tons

36 horse will give 6 290

113 " With”one of 740 tons 30

6 240

11

8

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We have already given an account of this system, and stated in a general way our reasons for considering it entirely fallacious; but what has before appeared in our pages may be considered as only a suitable introduction to the more elaborate and complete examination which we now publish from the pen of a gentleman, whose name, if we were at

liberty to mention it, would be at once recognized as that of one of the highest living authorities in all matters relating to steam navigation. We are glad to find that the writer's opinion of Mr. Booth's system coincides so entirely with our own.--Ep. M. M.

† An evident mistake.

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Charnock says the "sailing of a vessel seconds, (the cord attached to the boat, and depends on a myriad of circumstances." the cord attached to the weight, passing No table founded on actual performance round pulleys of the same diameter.”) of different vessels can be minutely

“No. 2. Other things being the same, I accurate ; and this of Mr. Seaward, ex

increased the weight, till it fell 7 feet 6 cept in the second instance, (which differ

inches in 3 seconds, the weight being then ing so materially from the three following

8 lbs." must have been misquoted,) gives prac

This, as Mr. Booth says, accords with the tical confirmation of the received theory.

' quadruple ratio, or of double speed requirThe results of the experiments of Colonel

ing octuple power." Beaufoy, although, they will doubtless be

But Experiment No. 3 gives vastly differfamiliar to your scientific readers, may

ent results. This was so arranged, that the

weight or power should always more through with propriety be submitted here for

the same space in the same time; the cord inspection, and the accompanying extract attached to the boat was passed round a from his table will show how nearly prac pulley twice the diameter of the pulley round tical experiment and theoretical deduc which the cord attached to the weight was tion coincide. 6. The scale on which passed: the boat would, consequently, move these experiments were conducted, the through the water 15 feet, while the weight, extreme accuracy observed, the ample as before, moved 7 feet 6 inches. means possessed by, and the extraordi • By repeated trials," Mr. Booth says, nary devotedness to the science, and the "I found that 5 pounds sufficed to draw the perseverance of the experimentalists are

boat 15 feet in 6 seconds, the said weight certain guarantees that the results may be

falling 7 feet 6 inches in the same time;' depended upon."

“thus by changing the mode of applying The law in hydrostatics governing the

the power, 5 pounds become as effective as

16.” “That is, 2} times the power, moving theory of resistance, is that, "if any body move through a fluid at rest—or the fluid

through the same space in the same time, was

required to draw the boat double the space move through the body at rest, the force

in the same time, or twice the distance at or resistance of the fluid against the body twice the speed.” will be as the square of the velocity and Experiment No. 4 confirms the “quadru. the density of the fluid.” And what can ple ratio.” No. 5 and 6 accord with No. 3. be more plain than the demonstration ? And with these six esperiments, (he says " For the force or resistance is as the he made others of a similar kind, with quantity of matter or particles struck,

which he will not trouble the reader,) he and the velocity with which they are sets up the doctrine, that all received struck. But the quantity or number of

opinions founded on theory and practice particles struck in any time are as the velocity and density of the fluid-there * On the new theory, 5 lbs. are as effore, the resistance, or force of the fluid fective as 16 on the exploded one. Acis as the density and square of the velo cording to it, a boat placed in a tide-way city.” Founded on this law of quadruple of 5 miles an hour, with a power on resistance, that of octuple power is the board of 30 horses, which exerted would necessary, consequence, for in a current just enable her to stem the current and of 10 miles an hour, double the number hold her own, would be driven against of particles must impinge and pass the this tide of 5 miles another 5 miles, by vessel, as in one of 5. The velocity and the addition of 45 horses ; 45 is, theredensity of the fluid are both doubled, fore, to effect the same speed in a curthe square of which gives the octuple rent of 10 miles that 30 has done in one ratio.

of 5! To this law and its consequences Mr. Now, let us imagine, for the sake of Booth demurs, and for the purpose of illustration, that a 30-horse engine, by testing it, he caused a trough 26 feet lorg. increasing the effective force of the steam, 3 feet wide, and 2 feet deep to be con may be converted at pleasure into a 60, structed, which was supplied with 18 120, and 240-horse power. Making the inches depth of water.

same number of revolutions, double the As many of your readers may not have quantity of steam must be expended in access to the book, I must trespass on the 60 that is required for the 30; and your space by giving his experiments. at double speed, 10 miles an hour instead

“ No. 1. A weight of 2 lbs. falling 7 feet of 5, four times, making it an engine of 6 inches drew the boat 7 feet 6 inches in 6 120 horses. But there is yet another

are erroneous.

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