12. If there be a spring affording but a small quantity of water, or having but a small fall, it is possible by the loss of some of the water to raise the rest to supply a gentleman's seat, or any place where it is wanted; but in a less quantity than what runs waste, if the place to which the water is to be raised is higher than the spring or reservoir from which the water falls. Schottus long ago contrived an engine for this purpose: but the first who put such a thing in execution. was Gironimo Finugio, at Rome, in 1616; and the first in this country was George Gerves, a carpenter, who, in the year 1725, erected an engine called the Multiplying-wheel Bucket-engine, at the seat of Sir John Chester, at Chichley, in Buckinghamshire. This engine was much approved by Sir Isaac Newton, Dr. Desaguliers, and Mr. Beighton, and was certainly very ingenious. The water from a spring descended in a large bucket hanging by a cord from an axle, while a smaller quantity was raised from the same place by a cord hanging from a wheel on the same axle: a fly and other regulating apparatus were added, to make the engine work itself, which it did for many years without being out of order. a whole, however, the contrivance is complex; and we are not aware that any other engines of the same kind have been erected. A description, with a plate, may be seen in Desaguliers's second volume.

As

Mr. H. Sarjeant, of Whitehaven, contrived a very cheap engine for raising water, for which the Society for the Encouragement of Arts awarded him a silver medal in the year 1801. A sketch of this simple invention is given in fig. 2. pl. XIX.

This engine was erected at Irton-hall, which is situated on an ascent of 60 or 61 feet perpendicular height: at the foot of this elevation, about 140 yards distant from the offices, there runs a small stream of water; and, in order to procure a constant supply of that necessary fluid, the object was to raise such stream to the house for culinary and domestic uses. With this view, a dam was formed at a short distance above the current, so as to cause a fall of about four feet: the water was then conducted through a wooden trough, into which a piece of leaden pipe, two inches in diameter, was inserted, and part of which is delineated at A.

The stream of this pipe is directed in such a manner as to run into the bucket B, when the latter is elevated; but, as soon as it begins to descend, the stream passes over it, and flows progressively to supply the wooden trough or well, at the foot of which stands the forcing-pump c, being three inches in diameter.

D is an iron cylinder attached to the pump-rod, which passes through it: such cylinder is filled with lead, and weighs about 240 lbs. This power works the pump, and forces the water to ascend to the house through a pipe one inch in diameter, and which is 420 feet in length.

At E is fixed a cord, which, when the bucket approaches to within four or five inches of its lowest projection, extends, and opens a valve in the bottom of the vessel through which the water is discharged.

An engine in a great degree similar to this was erected some years ago by the late James Spedding, esq. for a lead mine near Keswick, with the addition of a smaller bucket which emptied itself into the larger near the beginning of its descent, without which addition it was found that the beam only acquired a libratory motion, without making a full and effective stroke.

To answer this purpose in a more simple way, Mr. Sarjeant constructed the small engine in such manner as to finish its stroke (speaking of the bucket end) when the beam comes into an horizontal position, or a little below it. By this means the lever is virtually lengthened in its descent in the proportion of the radius to the cosine, of about thirty degrees, or as seven to six nearly, and consequently its power is increased in an equal proportion.

It is evident, that the opening of the valve might have been effected, perhaps better, by a projecting pin at the bottom; but Mr. S. chose to give an exact description of the engine as it stands. It has now been some years in use, and completely answers the purpose intended.

The only artificers employed, except the plumber, were a country blacksmith and carpenter; and the whole cost, exclusive of the pump and pipes, did not amount to 5.

In a letter, dated Whitehaven, April 28, 1801, Mr. Serjeant observes, that the pump requires about eighteen gallons of water in the bucket to raise the counter-weight, and make a fresh stroke in the pump; but it makes three strokes in a minute, and gives about a half-gallon into the cistern at each stroke. He adds, "I speak of what it did in the driest part of last summer; when it supplied a large family, together with workpeople, &c. with water for all purposes, in a situation where none was to be had before, except some bad water from a common pump which has been since removed. But the above supply being more than sufficient, the machine is occasionally stopped to prevent wear, which is done by merely casting off the string of the bucket valve."

13. Mr. Benjamin Dearborn, whose simple fire-engine has already been mentioned, has contrived an hydraulic engine

which may be conveniently added to a common pump, and thereby renders it useful in further elevating water, and particularly in extinguishing fires: the following description of his apparatus is extracted from the Memoirs of the American Academy.

Plate XIX. fig. 7. A, B, C, D, represents a pump, the form of which is similar to that of the pumps commonly employed on ship-board.

E, the spout.

F, a stopper.

D, d, a plank-cap, that is fitted to the pump, and provided with leather on its lower surface; being secured by the screws a,b in the centre is a hole, through which the spear of the pump passes, and round which a leather collar is made, as represented at the letter c.

:

g, a nut for the screw b.

f, a square piece of wood that is nailed across one end of the plank-cap, through both which the screw a is introduced: a hole is made through such piece and the cap, that communicates with the bore of the pump.

G, G, a wooden tube, which may be of any requisite length, and consist of any number of joints: it is made square at the lower extremity, and perforated for the reception of the cock; the upper end being made with a nice shoulder.

e, a wooden cock that opens or shuts the communication between the pump and the tube; being furnished on the opposite side with a handle and with a lock, in case it should be found

necessary.

h, h, are two ferules, the object of which is to prevent the tube from splitting.

н, H, braces, each of which ought to be crossed over another, as nearly at right angles as possible.

ii, are irons in form of a staple, which surround the tube, and pass through the braces; their ends being perforated with holes for fore-locks.

K, L, M, N, is a head made of five pieces of wood; k,l,m,n, a square piece, in the lower part of which is a hole for the reception of the extremity of the tube, and which piece rests on the shoulder o, p; to the lower end of this head is nailed a piece of leather, with a hole in its centre, similar to that made in the wood. Another piece of leather of the same form is placed on the top of the tube, and between both is a circle of thin platebrass; the two pieces of leather and the brass being pressed between the lower end of the head and the shoulder of the tube. Their edges are delineated at o, p.

K, N, and L, M, are the edges of two pieces of plank, of a

similar width with the head, to which they are closely nailed; each being provided with a tenon, that passes through a mortice in the end of the piece o, P: both tenons have holes for a forelock at q.

O, P, a piece of plank of the same width as the sides; the centre of which is perforated, in order that the tube may pass through; and in each end of which is a mortice for the reception of the tenons.

N, M, a cap.

7,7, are two pieces nailed to the side of the tube; the lower extremity of each is provided with a truck, with a view to lessen the friction of the head in its horizontal revolution.

q, q, represent fore-locks, the design of which is to fasten down the head, and prevent the water from escaping at the joint o,p.

Q, R, is a wooden conductor; the extremity marked with the letter o being solid, while the opposite end, R, is bored with a small auger.

s, a bolt that passes through the conductor and head, and being secured on the back with a fore-lock or nut: this bolt is rounded near the head, and square in the middle.

t,u,w, x, represents a piece of iron or brass, designed to prevent the head of the bolt from wearing into the wood. S, S, are ropes for the direction of the conductor. Fig. 8. represents the head without such conductor.

a, b, c, d, is a thick brass plate, the centre of which is perforated, so as to admit a passage to impurities, that might otherwise obstruct the conductor: for which purpose a piece of leather is nailed under it to the head. The square hole in the centre is adapted to the size of the bolt, which it prevents from turning. The conductor has a hollow cut round the bolt on the inside, of the same size as the circle of holes in the brass: round such cavity is nailed, on the face of the conductor, a piece of leather, that plays on the margin of the brass-plate when the conductor is in motion.

In the conclusion of his Memoir, Mr. Dearborn observes, that he has raised a tube of 30 feet on his pump; and, though the severity of the season had prevented him from completing it, so that one person only could work at the brake, yet he is enabled to throw water on a contiguous building, the nearest part of which is 37 feet from the pump, and between 30 and 40 feet in height.

14. The Hydraulic Ram, invented by M. Joseph Montgolfier, is a machine the construction of which is founded upon the acceleration of the velocity of a liquid mass falling in a tube, and the communication of that motion to another liquid mass

moving with a less velocity than the former. We know that a heavy body falling in vacuo runs over 16 feet in the first second; and a liquid column which falls in an unresisting vertical tube passes over the same space in the same time, with a motion uniformly accelerated: supposing this tube kept constantly full, and considering the friction of the particles of the fluid against one another, and against the sides of the tube, the motion is such, that, though it ceases to be uniformly accelerated, the velocity of the column, at first nothing, arrives by degrees at its maximum, in a longer or shorter time, depending on the dimensions and form of the tube; the contained fluid having acquired a certain velocity, there results a certain quantity of motion; the object of the hydraulic ram is to communicate a part of this motion to the mass of water which is to be elevated.

To understand the construction of this machine, suppose that an orifice is made through the pier or embankment of a reservoir of either standing or running water, at the depth of 4 or 5 feet below the surface of the fluid, such orifice receiving one end of a cylindrical tube about 20 or 24 feet long, the tube being formed of iron, copper, or other suitable materials, and placed horizontally, and firmly supported through its whole length by timber or by masonry. To the end of this tube farthest from the reservoir is adapted a piece of iron or of copper, called the head of the ram; it has two orifices, both of which open horizontally; the sucker of one of these closes by ascending, that belonging to the other closes by descending: these valves are guided in their motions by rings which traverse the handles attached to their centres. The orifice which has the ascending valve, and which is in fact the remoter orifice, permits the water to escape freely: the other is covered by a kind of tower, which serves as an air-vessel, and is pierced on one side by a hole to which a tube is adapted that is elevated to the height to which it is proposed to raise the water. See also ID, pl. XXXVIII.

To understand the action of the machine, let it be considered that when the remoter orifice is open, the water which runs along the horizontal tube will escape with a velocity which will continue to increase until the impression of the stream raises the valve and closes the orifice: hence the motion of all the water in the tube is suddenly stopped, and the vis viva acquired exerts itself on all parts of the tube, and consequently on the rising valve, which giving way permits the water to escape through it into the vessel above: the force existing in the cylinder being thus employed, the pressure to which the valve yielded becomes annihilated, and the sucker redescends, closing