Construction of a Pump.

air, the water will rise no higher by the first stroke; and the valve b, which was raised a little by the dilatation of the air in the pipe, will fall and stop the hole in the box H; and the surface of the water will stand at e. Then depress the piston or bucket from C to B, and as the air in the part B cannot get back again through the valve b, it will, as the bucket descends, raise the valve a, and so make its way through the upper part of the barrel d into the open air. But, upon raising the bucket G a second time, the air between it and the water in the lower pipe at a will be again left at liberty to fill a larger space; and so, its spring being again weakened, the pressure of the outward air on the water in the vessel K will force more water up into the lower pipe from e to f; and when the bucket is at its greatest height C, the lower valve b will fall, and stop the hole in the box H, as before. At the next stroke of the bucket or piston, the water will rise through the box H towards B, and then the valve b, which was raised by it, will fall when the bucket G is at its greatest height. Upon depressing the bucket again, the water cannot be pushed back through the valve b, which keeps close upon the hole whilst the piston descends; and upon raising the piston again, the outward pressure of the air will force the water up through H, where it will raise the valve, and follow the bucket to C. Upon the next depression of the bucket G, it will go down into the water in the barrel B; and as the water cannot be driven back through the now closed valve b, it will raise the valve a as the bucket descends, and will be lifted up by the bucket when it is next raised. And now, the whole space below the bucket being full, the water above it cannot sink when it is next depressed: but, upon its depression, the valve a will rise to let the bucket go down; and when it is quite down, the valve a will fall by its weight, and stop the hole in the bucket. When the bucket is next raised, all the water above it will be lifted up, and begin to run off by the pipe F. And thus, by raising and depressing the bucket alternately, there is still more water raised by it; which, getting above the pipe F, into the wide top I, will supply the pipe, and make it run a continued stream.

So, at every time the bucket is raised, the valve brises, and the valve a falls; and at every time the bucket is depressed, the valve b falls and a rises.

As it is the pressure of the air or atmosphere which causes the water to rise and follow the piston or bucket G as it is drawn up; and since a column of water thirty-three feet high is of equal weight with an equal column of the atmosphere, from the earth to the very top

Force Pump.

of the air; therefore the perpendicular height of the piston or bucket from the surface of the water in the well must always be less than thirty-three feet, otherwise the water will never get above the bucket. But when the height is less, the pressure of the atmosphere will be greater than the weight of the water in the pump, and will therefore raise it above the bucket: and when the water has once got above the bucket, it may be lifted thereby to any height, if the rod D be made long enough, and a sufficient degree of strength be employed to raise it with the weight of the water above the bucket.

The force required to work a pump will be as the height to which the water is raised, and as the square of the diameter of the pumpbore, in that part where the piston works. So that if two pumps be of equal heights, and one of them be twice as wide in the bore as the other, the widest will raise four times as much water as the narrowest, and will therefore require four times as much strength to work it.

The wideness or narrowness of the pump, in any other part besides that in which the piston works, does not make the pump either more or less difficult to work, except what difference may arise from the friction of the water in the bore; which is always greater in a narrow bore than in a wide one, because of the greater velocity of the water.

Should the disproportion between the suction-pipe and piston-barrel be very considerable, the labour of working the pump will be materially increased. Instances, however, have occurred, in which pumps have been so constructed as to raise cannon-balls by the momentum of the ascending column of water; and when hydraulic engines are constructed for the use of vessels, this mode of increasing the velocity of the water appears well adapted to prevent the pump choking or becoming foul.

The pump-rod is never raised directly by such a handle as E at the top, but by means of a lever, whose longer arm (at the end of which the power is applied) generally exceeds the length of the shorter arm five or six times; and, by that means it gives five or six times as much advantage to the power.

The forcing-pump raises water through the box H in the same manner as the sucking pump does, when the plunger or piston g is lifted up by the rod D d. But this plunger has no hole through it, to let the water in the barrel B C get above it, when it is depressed to B. and the valve b (which rose by the ascent of the water through the box H when the plunger g was drawn up) falls down and stops the hole in H, the moment that the plunger is raised to its greatest height. Therefore, as the water between the plunger g and box H can neither get through the plunger upon its descent, nor back again into

Force Pump.

the lower part of the pump Le, but has a free passage by the cavity around H into the pipe M M, which opens into the airvessel K K at P; the water is forced through the pipe M M by the descent of the plunger, and driven into the air-vessel; and in running up through the pipe at P, it opens the valve a; which shuts at the moment the plunger begins to be raised, because the action of the water against the under side of the valve then ceases.

The water, being thus forced into the air-vessel K K by repeated strokes of the plunger, gets above the lower end of the pipe G H I, and then begins to condense the air in the vessel K K. For, as the pipe G H is fixed air-tight into the vessel below F. and the air has no way to get out of the vessel but through the mouth of the pipe at I, and cannot get out when the mouth I is covered with water, and is more and more condensed as the water

rises upon the pipe, the air then begins to act forcibly by its spring against the surface of the water at H: and this action drives the water up through the pipe I H G F, from whence it spouts in a jet S to a great height; and is supplied by alternately raising and depressing of the plunger g, which constantly forces the water that rises it through valve H, along the pipe M M, into the air-vessel K K.

ODL

END OF VOL. I.

London: Knight and Bagster, 14, Bartholomew Close.

Dedicated, by permission, to the King's most excellent Majesty. THE BEAUTIES

OF

IRELAND:

BEING

Original Delineations,

TOPOGRAPHICAL, HISTORICAL, AND BIOGRAPHICAL,

OF EACH COUNTY.

BY J. N. BREWER, ESQ.

Author of the Introductory Volume to the Beauties of England and Wales, and of the Historical and Topographical Surveys of Oxfordshire, Warwickshire, and the County of Middlesex, forming Parts of the same Work.

ILLUSTRATED WITH NUMEROUS COPPER-PLATE

ENGRAVINGS,

REPRESENTING PUBLIC EDIFICES; CASTLES; CATHEDRALS; PAROCHIAL CHURCHES, EMINENT FOR BEAUTY, OR ANTIQUITY OF ARCHITECTURE; RUINS; PICTURESQUE SCENERY; SEATS OF NOBILITY AND GENTRY, &c. &c.

THE WHOLE OF THE ENGRAVINGS

BY J. & H. S. STORER,

AFTER ORIGINAL DRAWINGS MADE FOR THIS WORK, CHIEFLY BY MR. PETRIE, OF DUBLIN.

IT is universally acknowledged, that a Work descriptive of the Natural Features, and illustrative of the Topography and Antiquities of the whole of Ire~ land, is a desideratum in Literature. On this unexplored region, (for such it may be termed in regard to general delineation,) Nature has shed her richest varieties. The scenery displayed in many parts of the country may be said to realize the glowing pictures of a poetical imagination, and is allowed, by the few travellers with whom it is familiar, to equal that of the most admired districts of Switzerland and Italy. To the credit of Englishmen, FASHION is progressively leading the way to an examination and due estimate of charms so transcendent; and, until he has obtained an acquaintance with these latent beauties of the British Empire, no Englishman can be justified, on a principle of taste, in entering upon foreign travels in search of the picturesque.

The Antiquities comprise numerous Cromlechs; Funeral Tumuli; Military Earth works; some supposed unique vestiges of the Primitive Inhabitan

or their early Invaders; and round or pillar Towers, peculiar to Ireland, and equally curious in construction and mysterious as to original appropriation.

Descending to ages less remotely allied with existing manners, we find, in the remains of ancient Religious Buildings, many architectural beauties hitherto unnoticed, and some singularities of style, which induced a late distinguished writer (Mr. Gough) to assert that, "this country exhibits, in several tracts, a species of architecture by no means deformed, and yet differing exceedingly both from the Grecian orders, and from the Gothic style of building adopted in Britain."

The Topographer less recondite in speculation, has scarcely yet ascertained the extent of intelligence to be derived from a collection of the memorable circumstances connected with many Towns, Castles, and Noble Seats, possessing, whilst indistinct in the present gloom of neglect, a name that "stands more for number than account." Few countries are more affluent in topographical anecdote, for few indeed have experienced greater vicissitudes of fortune; and the peculiarities of manners, retained by a large part of the inhabitants, add to the interest and the value of local inquiries.

Impressed with these convictions, the Author of the Work now submitted to Public Notice has devoted to researches connected with the Topography of Ireland the literary amusement of several years. Whilst engaged in this pursuit, he has been honoured with the correspondence of some of the most able and distinguished residents in each of the four Irish provinces. But the most important assistance, as regards the Province of Leinster, has been derived from the extensive Manuscript Collections of his literary friend, Colonel Hervey De Montmorency, K. St. L. which have been unreservedly opened for his use, by that learned member of an illustrious family, long conspicuous in the annals of Ireland.

This Publication is intended to class with the BEAUTIES OF ENGLAND AND WALES, and will be comprised in Three Volumes, Octavo.

The First Volume, embellished with Twelve Engravings of Noblemen and Gentlemen's Seats, and other picturesque objects, in the Counties of Dublin, Clare, Cork, Kerry, Kildare, Kilkenny, Limerick, Queen's County, Meath, Roscommon, Tipperary, and Wicklow, is lately published, price 17. 4s. in boards, in demy 8vo. ; or on royal paper, with proof impressions of the plates, 17. 16s. in boards. For the accommodation of the Public who may prefer that mode of publication, the Work is also publishing in Monthly Parts (to be continued on the 1st of every month), price 4s. each; or on Royal Paper, 6s. The Second Volume is in great forwardness.

London: Printed for SHERWOOD, JONES, & CO. Paternoster-Row. Sold also by R. Milliken, J. Cumming, M. Keene, C. P. Archer, M. N. Mahon, R. M. Tims, B. Dugdale, C. La Grange, Hodges and M'Arthur, Westley and Tyrrell, and the other booksellers in DUBLIN; also by the booksellers in Waterford, Cork, Limerick, Clonmel, Coleraine, Newry, and Belfast.

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