421

value will be proportionably increased. Many months ago I described my apparatus to several engineers, but all doubted its efficiency. Having had a small engine (3-horse power) erected on my premises to which the safety-apparatus is attached, it affords me great satisfaction to state that it is completely effective, and may be made to suit any highpressure boiler.

Fig. 1 is a side view, and fig. 2/a front view of the apparatus.

A is a wrought-iron tube, one inch diameter, attached to the boiler, and connected with the cast-iron ball B, containing 28lbs. of mercury. When the pressure of the steam begins to act on the surface of the mercury, the level of which is at L in the ball and L in the tube of the front view, it is forced up into the glass tube in front of the scale, also into the wrought-iron tube at the back of the scale, shown at D in the side view. When it arrives a little above D, the wrought-iron tube is increased to 14th inch diameter inside, and admits of a cylindrical iron bar about ths of an inch diameter and 14 inches long, weighing 3lbs., which, with the balance-weight F hung above the tube, are 1lb. heavier than the damper G. The mercury continuing to rise, floats the cylindrical bar, and gives 1lb. preponderance to the damper G, which, of course, descends and moderates the draught; and as the pressure of the steam abates, the bar E falls with the mercury, and the damper rising, admits a more copious supply of air to the fire. The top of the tube D is made up solid at M, except a small aperture sufficient for the catgut cord, to which the cylindrical bar is attached at one end and the damper at the other. The pulley is 10 inches in diameter. Should any over-firing occur so as to raise the mercury above 18lbs., marked on the scale, which is the height the gauge is set in the annexed figure, the mercury will follow the tube H and fall into the wider tube I, where falling to the bottom, will be retained, and the steam will rush out at the top of the tube I, which may be continued through the roof of the boiler-house. When the steam has escaped, it is only necessary to open the cock N, and the mercury will run into the castiron ball B; and by shutting the cock after the mercury has run in, the apparatus will be again in the same state as be

fore, and will prove at all times an efficient safety-valve. The apparatus may be used for any pressure. The thumbscrew at K is for the purpose of drawing off the mercury to clean it when necessary. The glass tube C is open to the wrought-iron tube D, top and bottom, so that the height of the mercury is visible from top to bottom of the scale. The figures on the scale indicate pounds' pressure on the square inch.

My apparatus is open to the inspection of any gentleman or workman who may favour me with a call.

If the above is deemed worthy of insertion in your Magazine, your compliance will much oblige,

Yours, obediently,

EDWARD BUNTING.

Mansfield, March 19, 1836.

IMPROVED WINDOW-SASH.

Sir,-The public attention having been recently much attracted to the dangerous practice of employing servants, particu larly females, to clean the outsides of windows, often at a great elevation from the ground, an idea has suggested itself to my mind, by the adoption of which it seems to me that the difficulty now found in reaching the upper part of the outsides of windows might be easily avoided, and at little expense. The accidents which now so frequently take place, owing to the cause alluded to, certainly render it highly desirable that some means should be taken to prevent their recurrence. send you herewith a slight sketch of my plan, with an explanation, and should be

I

I am, Sir,

Your obedient, humble servant,
D. H. (No Mechanic.)
Pentonville, Jan. 30, 1836.

Explanation of the Engraving.

1. Hinges for the upper sash to turn upon.

2. Bolts to fasten or unfasten the sash. 3. Holes to receive the bolts.

4. Moveable partition to be fixed to the lower part of the frame by iron pegs. 5. Coping-stone.

A window-sash made upon the above plan may be cleaned inside and outside with perfect ease and safety. Let the lower part of the frame of the under sash, which now consists of one piece of wood, be made of two; and let these two pieces be fixed together by iron pegs, but so as to admit of their being separated as occasion may require. When the panes of the upper sash want cleaning on the outside, detach the moveable or under piece of wood of the lower sash, marked No. 4. The lower sash will then fall so as to allow the top sash to be opened without hindrance from the middle part of the frame. This is done by unbolting the upper sash, which will then open inside, the panes of which may be thus cleaned as often as necessary, without danger or difficulty.

your

RAILWAY HINTS.

Sir,-Some weeks ago you favoured readers with an account of Professor Barlow's experiments to ascertain the advantages or disadvantages of the chairs for rails being at three and six feet distance from each other. I wish Mr. Barlow's attention had been directed to solid platforms, so as to give the rails a steady bed throughout their length, as I suggested for slate platforms. I have re. cently heard that a railway from Bolton, or near Bolton-le-Moors, is now being made with a solid stone platform; perhaps some of your correspondents could procure you the particulars.

Before I saw your notice of the proposition for stopping the wheels on the Greenwich Railway, in order to produce friction on the rails to retard or stop the locomotives, I had been thinking on the same subject. I do not propose using the

purpose, but to have drags, or dragwheels, which can be let down in an instant on to the rails. I think it probable that the ordinary wheels would soon be spoiled if used in that way. I also propose friction-wheels to let down on the rails to enable a train to ascend an inclined plane. I propose to raise and force down these drag and friction wheels by means of screws. I would also suggest elastic fenders to precede the wheels of a train, or carriage with an engine, to turn off any obstacle from the railway, or any person who may happen to be in the way, to prevent, or at least to diminish, the violence of accidents.

I would further suggest, that for railways the motion of the engine should be given to a horizontal fly-wheel, which may be placed under the carriage, and the motion communicated to the wheels by hands and pulleys. The object of this is to prevent the jar now experienced. The bands may be inade tight or slack by means of a screw. If the latter, the action of the engine will be instantaneously taken off the wheels.

I am, Sir, your obedient servant, JOSEPH JOPLING. 31, Somerset-street, April 14, 1836.

CIRCULATING DECIMALS.

Sir, I think that your correspondent, Mr. Peacock, pp. 12 and 13, has taken a very partial view of the question to which he alludes, having only given a particular rule, and which fails when applied generally. For instance:-Given 3823529 to find the whole of the series. By the first part of this rule we certainly obtain the

whole of the series, 38235294117647058, but the second part fails completely. In this series 058 is of the least decimal value; divide unity by this, and we obtain. 17 for the denominator; or take the next in value, 1176, and we have 85, neither of which are correct, the equivalent vulgar fraction being 11.

I consider him to have fallen into this error from the property possessed, in some cases, by the denominator of the

1

fraction (where m is a prime number)

m

of containing within itself always the same progression of figures, whatever the

numerator may be; for instance, if we take any numerator for the fraction we shall always find the same figures constantly recur, and 0232, &c. being the equivalent for, we shall always find 0232, &c. recur in every multiple of the same. But the equivalent for,

294, &c. does not recur in the multiplication by the numerator.

From this we may draw the inference, that this rule only applies to those circulates where the circle commences with

the first figure, as '0232, &c., and fails when applied to those that commence with the second or any subsequent figure,

as 0294, &c. or 01086, &c. The first are called pure, the second mixed circulates.

In the course of my investigations of this subject, I noticed the following curious methods of obtaining the same result, which are equally applicable to all pure circulates :

Rule 1. Divide 999 ad infinitum by the given number.) 3.2

Divide the quotient ad infinitum by the given number, and observe that there are the same number of figures in each quotient.

From the last remainder obtained by the first operation, subtract the next preceding one for the numerator.

Proceed the same by the second for the

denominator. Thus:-4472 9999999 =2.8666

RECENT AMERICAN PATENTS. 39/19 (Selected from the Franklin Journal.) IMPROVEMENT IN THEODOLITE, ɛ Samuel Stone, Long Green, Maryland. The patentee states his improvement to be" in the art of measuring distances at one station with a theodolite, or any other instrument by which an angle can be made either perpendi cularly or horizontally," &c. The patent, › however, is taken for an improvement in instrument, and not in the art of using it.. He says, "the first improvement which

then

com

claim is the mechanical addition to the mon theodolite, by extending the diameter of the horizontal limb for the purpose of forming a surface as well as a centre on which circular rim or plate revolves, as already de scribed; and also the application of the logarithmic calculations as applied to the circle, as already described. But I particularly claim the improvement of measuring dise tances by an angle at one point or station, using the pole or stave, with its graduations, for one side of the triangle."

8

ed ton

With respect to its construction and use," the inventor says:

"This instrument embraces all the princio ples of a modern theodolite; besides which, it contains the following improvements The first improvement is a circular revolving plate, sliding or resting upon the limb of the instrument, the upper surface of which forms a plane with the upper surface of the limb; on which are delineated a set of mathematical numbers, which supply the place of a table of logarithms, and all other logarithmic

tables.

(0753

"In the second place, this instrument is so constructed as to supersede the necessity and use of a chain in all cases, The distance of any visible object can be ascertained at one station, as far as the flag-staff can be distinctly seen through the telescope of the instrument, to the exactness of chains, links, and decimals.

"It also calculates the latitude and departure of every course run, and the base and perpendicular of all elevations. It further embraces all the fundamental rules of common arithmetic, viz. multiplication, division, single rule of three, interest, mensu

&c.

end; of these there may be two, three, or

3.

Any question angled or oblique, can be solved on the instrument correctly; 3 including all questions that can be performed by logarithms or loga rithmic tables. The whole without the use of figures or a mathematical calculation."

The instrument has received the approba tion of the New York Institute, the managers of which have awarded their highest premium, a gold medal, to the inventor

IMPROVEMENT IN THE COMMON FIREPLACE, Ira A. Bean and Elijah Shinner, Sandwich, New Hampshire.—A box is to be formed across the fire-place somewhat like a hollow iron back-log; below this box or furnace there is to be an air-chamber, and a to rise vertically near its back edge,

Pas, with the chimney back, to form a flue

for the escape of smoke. In the top plate of the box there are openings for cooking utenan opening also for admitting

silsherehes to let heated air into the

fuel, and

way.

room, which, however, will never produce this effect, as the draught will be the other m is to the construction of the box in th hearth, and the arrangement and application of the same, with the flues, funnels, and false back, to common open fireplaces; the object of which is to save room and fuel, furnish a cheap and convenient apparatus for cooking, and at the same time avoid the impure air occasioned by close stoves, and the seam from cooking-stoves."

The whole of the above-named objects will not be attained by means of this contrivance; we do not think that there will be any special convenience in its use, and it certainly will not be economical when intended for heating in the place of a well constructed close stove..

MACHINE FOR WASHING AND CHURNING, Charles Otis, Finksburg, Maryland,

I make a revolving cylinder or barrel, which is to turn upon gudgeons in the usual way, and having an opening through which the articles to be acted upon may be introduced, and secured by a close fitting door, or shutter. I cause this barrel, or cylinder, to revolve in a trough which serves to eatch

ny suds that may be allowed to escape, and which, in the churning of butter, may be filled with water, either warm or cold, according to the season of the year, and thus facilitate the operation. The parts thus far described I do not claim as constituting any part of my invention, the same having been repeatedly constructed by others; but whatI do claim is the following appendage within the revolving cylinders:-I place flat wings, or buckets, on the inside of the periphery of the cylinder, extending along from end to

باشد

D

which stand in the directions of radii to thei cylinder. These boards may vary in width w from two to six inches, more or less, accord-s ing to the size of the machine, and I some times perforate them with holes, to increase, the agitation of the fluid. They also server to lift the clothes and suds in washing, or the cream in effectually than the

have

pins wurnimetimes been yed chat purpose. I confine my

for

ex.

to the employment of the wings, or buckets, herein described.

FOR

IMPROVEMENT IN FIRE-PLACES GRATES TO BURN ANTHRACITE, Joseph Snyder, Pennsylvania.-The greater part of this fire-place is proposed to be made of y cast-iron; the bottom of it is formed of two parallel plates, two or three inches apart, and constituting a part of a circulating flue. This may stand upon feet, raising it a little from the ordinary hearth, and on it rests the back and jambs, the back also being formed of double plates, connecting with those at the bottom. The grate is situated as is usual in open fire-places, and above it are double top-1 plates also forming a flue between them!! Hollow columns at the corner of this fireplace, in front, connect the hollow hearth with this hollow top, the back end of which passes into the chimney, in the manner of a Franklin stove; there is a damper situated on the lower plate of the upper base, which being opened allows of a direct draught into the chimney, but when closed, causes it to circulate around the whole structure. The grate is lined in the usual way, and supposing the damper to be closed, the draught is over the sloping back into the back flue, then downwards between the two back plates, then forward in the hollow hearth, and upward through the columns into the cap flue, and back into the chimney. The claim is to "the principle of diffusing the heat of ang open fire-place or grate to the hearth and parts situated below the fire, by a descending and ascending flue, or flues, and double hearth, as set forth and described."

THRASHING MACHINE, Thomas Rucker, jun., of Murphreysborough, Tennessee, assignee of Pendleton Check, of the same county. In this machine there are two revolving cylinders, one placed over the other other; the upper one is furnished with knives or cutters, acting against an opposing, fixed, cutting edge, and these together operate in the manner of shears. The grained ends of the sheaves are fed to this cutting apparatus, and the pieces cut off fall between a thrashing cylinder and a concave, grooved from end to end, in the form of saw teeth, by which the

46

grain is thrashed out. The claim is to" the manner of separating the heads of wheat or other grain from the straw, previous to thrashing it by the combination of machinery herein specified and described." It is said that in this instrument "the wheat is thrashed out more completely, and with far less labour than in those machines where the whole sheaf is operated on."

PUMPS AND FIRE-ENGINES, H. Gutes, Northampton, Massachusetts.-The body of this pump is to be a short cylinder or drum, its axis standing horizontally, and truncated or cut off on its upper side so as to reduce it to about two-thirds of its cylindrical capacity; this upper part is covered, watertight, by a horizontal plate. An axis passes through the cylinder, and has attached to it two buckets or leaves, standing at right angles to each other, fitting the lower part of the cylinder and the two heads, water tight, to effect which they are made of durable metallic plates, screwed together with packing between them. Each of these leaves has a valve opening outwards, or towards the upper plate of the chamber.

The upper part of the drum is divided into two chambers by a fixed partition descending from the upper plate to the upper side of the vibrating axis, against which it is to fit water-tight. There are two valves opening upwards on the top plate, one on each side of the partition, and these are both covered by a conical delivery-pipe, by which the water is to be conducted as required. The receiving-pipe descends from the bottom of the chamber into the reservoir, or chamber.

The axis is to be made to vibrate about a quadrant of a circle, and those acquainted with hydraulics will see, that if the instrument be in good order, water will be raised by it. The construction of a pump, operating as described, is claimed. We could point to very similar plans of pumps, but we do not think it necessary to touch this point. Such pumps, if made with extreme care, will work promisingly at first, but they will soon go out of order. When in the best condition, we do not believe that such a pump is equal to the common piston and cylinder, the direction of the water being quite as much changed in it.

AN AUGER, William Jones, Portsmouth, Virginia. The specification of this invention is brevity itself exemplified; it consists of the following words:" This improvement is a hollow auger made so as to embrace the bolts or fastenings in ships or vessels, and to cut the wood from around them, by which means the plank, &c., can be removed, without the delay, trouble, and expense, usually required by splitting them out."

In the drawing, the auger is represented as twisted like the ordinary screw auger, but capable of allowing a bolt to pass within it. This must be a very useful thing, and, so far as we know, it is new.

MACHINE FOR CUTTING SAUSAGE MEAT, AND STUFFING SAUSAGES, Abraham and John Keagy, Pennsylvania.-The cutting is effected by means of a cylinder, around which are placed knives which we usually make of a triangular form, one of the sides being in contact with the cylinder. This revolves within a concave, or hollow cylinder, furnished with similar knives so placed as net to interfere with those on the cylinder. These knives are but placed somewhat obliquely, so as to stand in the direction of a spiral around the cylinders. The revolving cylinder has its axis placed horizontally in a box, the sides and ends of which are enclosed excepting where the meat is admitted and discharged. A gudgeon projects through the box at one end to receive a crank or wheel to turn the cylinder.

The opening for feeding is on the upper side, and at one end of this box; and this opening is surmounted by a vertical trunk, which may be in the form of a parallelogram, of the width of the lower box, and about half its depth, more or less. A piston, or follower, is adapted to this feeding trunk, or hopper, from the middle of which a rod rises, operating as a piston rod, being acted upon by a lever, worked like a pump-handle. The piston rod passes through the lever, and has a rack, or notches, upon it, which engage with the lever in its descent, but allow it to rise without raising the piston, so that the meat put into the feeding-trunk is forced down by each successive stroke. To facilitate the passage of the meat into the horizontal, from the vertical trunk, I form a spiral excavation in the hollow cylinder, immediately under the vertical trunk; which operates as an inclined plane in producing the desired effect. The cut meat, when it arrives at the extreme end of the cutting cylinder passes out through an opening in the bottom of the box. When the feeding-trunk is to be replenished, the lever may be turned back on its joint, and the piston removed, leaving the opening perfectly free.

When the cutting has been completed, the vertical trunk, with its piston, is used for the purpose of stuffing. To effect this, a shutter, or slider, is slipped into its place where it forms a bottom to the vertical, and cuts off its communication with the horizontal trunk, and a tin, or other tube, of proper size, is fitted into an opening prepared for it on one side of the trunk, at its lower end,