TAYLOR'S PATENT BOILER FEEDERSEAWARD'S PATENT STEAM-SAVER -WHITE LAW'S FEED PUMPS.

Sir,-On inspection of the Patent Boiler Feeder in No. 768, it appears to be nearly identified, the float excepted, with an apparatus patented some time since by Mr. Samuel Seaward, as a steamsaver for marine engines, having other important objects likewise in view, but which it seems has not been brought into common use, probably on account of the personal attention required by the cocks when the apparatus is in action

The plans agree so far as the close cistern placed over the boiler, and the steam and water cocks, are concerned.

Now as to the action of the feeder, I really cannot see the advantage of its employment in land engines, unless to meet some local consideration-which requires to be stated-and in such case

there will be an inevitable loss of heat from the admission of steam to the surface of the water while the boiler is supplied by the lower portion, to which the heat is slowly conducted, and whence the supply is admitted to the cistern to meet the next demand of the boiler.

What can be more simple than the long established method of regulating the supply of water in land engine boilers by the float, and valve acted on thereby? Certainly, if I understand it rightly, Taylor and Davis's patent steam boiler feeder will never supersede it, and for marine engines it is out of the question.

The inclosed sketch and description of the "steam saver" alluded to, from Mr. Seaward's specification, may be thought worth your consideration from its novelty of application, if it has not already appeared in your most useful journal.

"I cause a vessel Z, of iron or other suitable material, and capable of withstanding the heat of the steam contained in the boiler Y, and of resisting the pressure of the atmosphere, and of a capacity equal to onetwentieth of the water chamber of the boiler, or thereabouts; this vessel I call a receiver, and it is to be placed on the said boiler Y, as shewn in the drawing, or any where near the boiler, of a sufficient height, that any fluid contained in the said receiver, will descend by its own gravity into the steam boiler. To this vessel I attach four cocks or valves, and as many pipes, in the following order, viz.: one pipe A, from the top of the vessel Z, to the steam chamber of the

steam-boiler; one pipe B, from the bottom of the receiver Z, to the water chamber of boiler; one pipe C, from the bottom of the said receiver to the water outside the ship; and one pipe D, from the top of the said receiver, to the well or lowest part of the ship in which the boiler is placed.

"The first operation of this apparatus for the effecting the saving of fuel is as follows: -When the steam is so high as to raise the safety-valves, and escape, either in consequence of the engines standing still, or the too great quantity of fire, the cock A is to be opened, and the receiver Z filled with steam, the air rushing out by a small cock E, placed at the top. The receiver being

full, the cock A is to be shut, and also the cock E, and the cock C opened; the steam contained in the said receiver will by this operation be condensed, and a partial vacuum thereby be formed; the water will then rush from outside the ship, and fill the receiver; the cock C being then shut, and the cock B opened, the water will descend slowly by its own gravity into the water chamber of the boilers; and this can be accelerated by again opening the cock A, by which means the water will descend at a heat not much below that of boiling water. The saving of fuel will be evident, because, at all times, the boiler may be completely filled, and the water itself raised to a high temperature by the steam, which would otherwise escape at the safety valves, and be completely lost.

"The second operation is that of pumping or drawing the water from the hold of the ship. To effect this the cock A is again opened, and the receiver thereby filled with steam; upon closing the cock A, the cock D is opened, and the water will rush up from the hold of the ship, and fill the receiver; the cock D being shut, and the cock C opened, the water contained in the receiver will run overboard, by opening the small air cock E in the top. This operation can be repeated till the ship is perfectly dry: fifty or sixty tons of water per hour can be discharged with great facility in a boat of 100 horses' power, by simply employing the spare steam while the engines are at rest."

99.66

Since writing the above, I received No. 769, with a frontispiece and description of another feeding apparatus, to be worked by a separate steam-engine! with "chests,' casings," "slide valves," and other details, which are left out to avoid complexity! (vide sketch) which certainly displays much ingenuity, and is intended as an illustration of their application to marine engines. It would appear that Messrs. Taylor, Davis, and Whitelaw have taken a great deal of pains, the latter gentleman especially, in contriving to meet a defect in the steam-engine which exists but in imagination.

I have already remarked on the simplicity of the existing apparatus in ordinary land engines, with the feed head or equilibrium pipe; and where steam of high pressure is used, the feed-pump forces the water directly into the boiler, regulated by a stop-cock and loaded valve, through which the surplus is conveyed to waste; and in many places a cock is fitted to the suction pipe of the pump, so as to regulate the supply by admission of a portion of air, and thus dispensing with

the loaded valve, which passing into the boiler with the feed, is no doubt objectionable in condensing engines.

In many cases the height of water within the boilers is regulated by a float acting on the stop-cock before mentioned.

Now in marine engines, from the constant fluctuation of the height of water in the boilers, both from the influence of the sea, and from the necessity of accu mulating water for blowing off, and diminishing the same in performing the latter operation, experience has shown that the ordinary feed pump, with its stop-cock and loaded value, is the most simple and efficient contrivance: all schemes for regulating the feed by floats, &c., having been abandoned long since as unsafe from their liability to throw the engineer off his guard, who might place too much confidence in their doubtful performance.

It appears moreover that the precision of Mr. Whitelaw's feeder mainly depends on the compression of a certain bulk of steam, admitted at each stroke of his slide valve-compression of steam (that is, increasing its elastic force) by injection of a charge of comparatively cold water! Surely Mr. W. must have lost sight of the fact, that his feed will be cold in the case of a high pressure boiler, or nearly so, and will not be above 100° if discharged from the condenser of a low pressure engine; so that on the outset his principles are mistaken, without reference to the absurdity of employing a supplementary engine, with its additional cost and expense of maintaining.

Now Taylor and Davis's plan would effect that which Whitelaw's engine is expected to do, under all circumstances, with the advantage of greater simplicity at least, to recommend it. I am, Sir,

Your most obedient servant,
NAUTICUS.

Woolwich, May 7, 1838.

the appearance of those interesting particulars which Mr. B. (when he announced his discovery, eighteen months ago), led them to suppose would be published in its pages?

I cannot but express surprise at the very nonchalant way in which Mr. Baddeley speaks of his plan, even in the same paragraph which states his continued confidence in its perfect practicability. One would imagine that few "more pressing engagements" would be allowed to stand in the way of introducing to the world an invention which would instantly take its place as one of

the most important of modern times,
and infallibly immortalize the name of
its discoverer into the bargain! At any
rate, if only to silence the incredulous
many, who may be apt, on this occasion
as on others, to insinuate that what
seemed perfect in theory has failed in
practice, it would surely be worth Mr.
Baddeley's while to make public the de-
tails of his scheme at once.
I remain, Sir,

Your obedient servant,
PHILO-BADDELEY,

London, May 2, 1838.

A B C represent an instrument similar to a pair of compasses, the legs of which are moveable on the joint C; the leg BC is somewhat longer than A C; the latter is a cylindrical piece of hard steel wire pointed at the end; t is a hollow tube which slides up and down the leg A C; to this tube is attached the piece DE P, having two joints to allow the pencil P to be placed in a position parallel to the leg A C; there should be a milled-headed screw at each of the two joints D and E to make them tight when adjusted to any given position.

B

To describe an ellipsis, place the point A on the centre of the ellipsis, the point B must be placed on the continuation of the longer diameter, then open the point

P till the pencil coincides with the end of the shorter diameter, turn the tube a quarter round, and if the pencil should not coincide with the end of the longer

diameter, it can easily be made to do so · by moving the point B either nearer to or farther from A in the line A B till it does coincide; this being done, turn the clylinder round by the milled-head; this in combination with the sliding motion will cause the pencil to describe a true ellipsis. The ellipsis described is an oblique section of a cylinder made by the plane of the paper, the point of the pencil been always in the surface of a cylinder the radius of which is equal to the distance of the pencil from the axis. The ellipsis described is as true as any one produced by the section of a cone. This plan answers very well when the ellipsis required is not very excentric, that is, when it does not require the leg AC to make an angle with the paper much less than 45 degrees, which limits its use. I send it to you, imperfect as it is, in hopes that some of your readers may improve upon it.

I. R. A.

THE LOSS OF POWER BY THE CRANKS OF STEAM-ENGINES.

Sir, I have not read the former papers on this subject, nor do I believe it necessary, to enable me to point out an error into which Mr. Oxley appears to have fallen-his not admitting into his calculation the space moved over by the crank pin, as compared with the piston of a steam-engine, which is for a whole stroke, as much more than that moved over by the piston, as the circumference of a circle is greater than two diameters, which for half a stroke is the half of 31416 or 15708. Although Mr. Oxley may be, and is, in a rough way, correct with regard to the leverage of the crank being diminished from 100000 to 62142, yet by multiplying by 15708 we have 97612, which is within 1-25th of the whole amount. This difference arises, no doubt, from want of greater nicety in calculating the length of the leverage, or average of sines, a defect which Mr. Oxley, no doubt, with his extensive mathematical knowledge, will be able to supply. W. H. T.

RECENT AMERICAN PATENTS. (Selected from the Franklin Journal for Dec. 1837, and Jan. 1838.)

A REGISTER AND AIR BOX FOR ADMITTING THE AIR TO FIRE PLACES, Allan Pollock,

Boston, Massachusetts.-This is a contrivance intended to regulate the admission of air from without the room, to feed the fire contained in a grate. The box described may be made of cast iron, and it is to be built into the chimney in setting the grate, in such a way that the bottom of the box shall rest upon the hearth, its front edge being even with the back of the grate, and extending up from the hearth to the grate, thus occupying the ordinary position of the chimney back under the grate; this front side of the box is entirely open. The depth of it from front to back may be about six or eight inches; the back plate is to be perforated, near its lower edge, with four holes, more or less, say of two inches in diameter, which holes may be simultaneously opened or closed by a sliding register, allowing air from without the house, or from a cellar, entry, &c., to pass through the openings in regulated quantities. A lever attached to the register extends to the front of the fire place, serving to move it at pleasure. To prevent ashes, &c., from coming into contact with the register, or from being blown into the room by the entering draught, a partition extends from the bottom along the whole length of the box, about midway of its depth, and rises to within twoinches of its top.

The claim is to "the register with two or more spaces, apertures being so placed that by moving the register the corresponding apertures in the back of the box may be opened or shut simultaneously; also the air box with the middle partition intended to change the direction of the current of air, so as to prevent the dust and ashes from being blown into the room."

IMPROVEMENTS IN THE PROCESS OF BURNING LIME, Samuel Garber, and H. Swartzengrover, Norristown, Pennsylvania. -"We take (say the patentees,) a kiln of either of the ordinary constructions for the

burning of lime, and we adapt thereto any of the various kinds of blowing apparatus used for forges, or for furnaces, and after having charged our kiln with lime-stone and fuel in the usual way, and ignited the fuel, we introduce a blast of air into the same, giving to the blast such a degree of force as may be foundrequisite. The blowing apparatus which we prefer, is the ordinary fanwheel, as it affords, at once, a more diffused blast than that from bellows, or from blowing cylinders; but by the adoption of proper means, well known to machinists, as by blowing into a regulator, and by introducing the blast through several openings as large as may be found convenient, the blast may be sufficiently diffused from any blowing apparatus.

It is well known to those persons employed in the business of burning lime, that

the operation of a kiln is much influenced by the state of the weather, the fuel sometimes burning too feebly to produce a sufficiently high temperature; but by means of the artificial blast, the process is made to go on independently of the atmospheric changes, and the proper temperature is rapidly attained. By this procedure, the saving of fuel is large in amount, as the proper degree of heat can not only be produced but also maintained, until the calcination is completed; and furthermore, we are enabled to burn such fuel as would either be thrown away, or would be rejected as unsuited to the burning of lime in kilns without the bast."

The patentees claim the introduction of wind into a lime kiln, by a blowing apparatus, for regulating the combustion of the fuel, and, in consequence, the calcination of the lime.

The

STRAW CUTTER, Henry Silliman, New York. This straw cutter is peculiar in its construction, presenting in this respect more novelty than is usual in machines for this purpose. The part in which the straw is to be placed, consists of a hollow cylinder standing horizontally upon a suitable frame. The interior of this cylinder is to be divided into several compartments, say four, by partitions running the whole length of it. cross section of each compartment would, in this case, be a quadrant; but the inner angle of this quadrant is cut off in consequence of the passing of a screw, through a tube or case occupying the axis of the cylinder. The cutting knives are fixed upon the face of a wheel at one end of the cylinder, which is open, and as this wheel revolves, the screw with which it is connected, also revolves, and carries a nut which moves back and forth within the centre tube. From this nut, rods project out at the back end of the cylinder, which rods are received and attached to pistons, or followers which fill the compartments, and serve to force the straw forward. Each compartment is furnished with a door, which is opened to supply the straw when requisite. The cylinder may be turned round in its frame, to bring the doors successively to the top.

The claim is to the manner of acting upon the pistons, by which the straw is fed to the cutting knife, or knives, by the intervention of a revolving screw, carrying a nut backward and forward, and with it the rods and pistons, substantially in the manner and for the purpose set forth.

MANUFACTURE OF WHITE LEAD, Peregrine Phillips, Campbell county, Kentucky. -The lead is to be rolled into sheets, or shotted, but it is preferred to be feathered, that is, granulated, by pouring it, in a small

stream, into water. The prepared lead is then to be placed in a vat with a perforated false bottom at about its middle, where the lead is to be sustained. A pump is to be placed so as to pass through the false bottom, or in such manner as to allow the liquid contained in the vat to be pumped up. A steam pipe, of pure tin, &c., is to pass once, or more times, round within the vessel; and a tube through which air may be blown, is also to pass into the vat, below the false bottom. Distilled vinegar, or dilute acetic acid, containing about two or three per cent of dry acetic acid, is then to be poured into the vessel, to such height as not to interfere with the passage or air through the feathered lead. The pump is then to be worked, and the liquid to be so distributed by it as that the lead shall be kept constantly moistened. The acid may be kept at a temperature of 85 or 90 degrees by the passing of steam through the steam pipe. A blowing apparatus is to be kept at work at the same time, throwing in atmospheric air, to oxidize the lead as it passes up among it, which oxide will be dissolved by the acid, forming an acetate. When saturation is perfect, the fluid is to be drawn off into a cooler, and a fresh portion supplied to the lead, and this repeated until the whole is dissolved. The saturation may be judged of by the specific gravity ceasing to increase.

The saturated liquid is to be put into a vat, called a carbonating vat, constructed like that for saturating, but, instead of lead, having twigs, or pebbles, &c., upon the false bottom. Upon this brushwood, &c., the saturated liquid is to be pumped, whilst a quantity of carbonic acid, or a mixture of it with other air, is to be forced into the vat below the false bottom, which as it passes up, will convert the acetate into a carbonate, and this, being insoluble, will fall to the bottom in the form of an impalpable powder. When the precipitation ceases, the liquid is to be drawn off, and used again in the first vat, and so on continuously. The precipitated lead is to be thoroughly washed, then dried, and the process is completed.

The whole apparatus used is clearly described, and full estimates are given of the respective ingredients necessary to produce the desired reaction. The following are the claims: -

"I claim as my own invention, first, the oxidation of the lead, and dissolving of the said oxide by means of pumping or throwing diluted acetic acid, or vinegar over lead when in a state exposing a large proportion of surface, at the same time drawing, or forcing, a current of atmospheric air through the interstices of the said lead; and I claim this only for the purpose of preparing a