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place, and it has been successfully used. It acts action. Of these, as the most important, we shall mechanically by its great absorbent powers. describe in detail the following: 1. The Lift or
PU’MA, or COUGAR (Felis concolor, Leopardus Suction Pump; 2. The Lift and Force Pump; 3. concolor, or Puma concolor), one of the largest of The Chain-pump; 4. The Centrifugal Pump; 5. the American Felida, rivalled only by the jaguar.
The Jet-pump: It is sometimes called the American Lion, although
1. The Lift or Suction Pump.—The diagrams it is more allied to the leopard, notwithstanding figs. 1 and 2 represent the ordinary suction pump. its want of spots and stripes. It is from 4 to 48 A is a cylinder, which is called the barrel ; with it is feet in length from the nose to the root of the tail, connected at the bottom a pipe, B, which communi. and the tail about 2 feet or 24. The fur is thick cates with the water to be raised; and at its top is and close, reddish-brown above, lighter on the sides, another pipe, C, which receives the water raised. and reddish-white on the belly; the muzzle, chin, In the barrel are placed two valves, D and E. D is throat, and insides of the legs grayish-white, the fixed in position at the bottom of the barrel; E is breast almost
pure white. Young pumas have darkbrown spots in three rows on the back, and scattered markings elsewhere, exhibiting the relation to the leopards. The long tail of the P. is covered with thick fur, and is generally coiled up, as if it were prehensile, which it does not seem to be, although the P. climbs trees very well, and often descends on its prey from among their branches. The P. was formerly found in all except the coldest parts of America, but is now rare in most parts of North America, having been expelled by man. It rarely attacks man, but is very ready to prey on domestic animals, and seems to have a thirst for blood beyond that of other Felidæ, one P. having
F been known to kill 50 sheep in a night, drinking a little of the blood of each; a very sufficient reason for the anxiety which all American farmers shew for its destruction. Yet it is easily tamed, and when tamed, a very gentle creature, urring like a cat, and shewing equal love of attentions. The geographical range of the P. extends far south
B wards in Patagonia, and northwards even to the state of New York, although it is now very rare in all long-settled parts of North America. It is the Painter (Panther) of North American farmers. It sometimes issues from the forests, and roams over prairies and pampas, and is not unfrequently
H caught by the lasso of South American hunters. A BLACK P. (Felis nigra of some naturalists), a doubtful species, and probably only a variety of the common P., is found in some parts of South America. PU'MICE, a mineral found in volcanic countries,
Fig. 1. generally with obsidian and porphyries. In cheinical composition, it agrees with obsidian, of which attached to, and forms part of the piston F, which it may be regarded as a peculiar form, rapidly
moves up and down the barrel when motive-power cooled from a melted and boiling state. It is of a is applied to the rod G. The piston, or bucket, white or gray colour, more rarely yellow, brown, consists of a cylindrical piece of wood or metal, or black ; and so vesicular, that in mass, it is which fits exactly the barrel in which it moves, lighter than water, and swims in it. The vesicles, or cells, are often of a much elongated shape. P. ference and the sides of the cylinder. This tight
so that no water or air can pass between its circumoften exhibits more or less of a filainentous structure; and it is said to be most filamentous them with a leather ring; and in those of metal, by
fitting is attained in wooden pistons by surrounding when silica is most abundant in its composition. hemp or other packing, which is wrapped round a It is very hard and very brittle. It is much used for polishing wood, ivory, metals, glass, slates, interior of the piston is closed at the top by the
groove made in their outer surface. The hollow marble, lithographic stones, &c., and in the pre: valve E, which is a kind of door opening on a hinge, paration of vellum, parchment, and some kinds of at one side of it, in an upward direction, on the leather. Among other purposes to which it is applied is the rubbing away of corns and callosities. application of pressure, and shutting on to its seat Great quantities are exported from the Lipari Isles on the piston when the pressure is removed. When to Britain and all parts of Europe. The Lipari opened, water, or air can pass through it to the
upper side of the piston; but when shut, none can Isles are in great part composed of P., which there, pass from one side of the piston to the other. The as in some other places, occurs as a rock. P. is the other valve, D, is similar to it in all respects, except chief product of some volcanic eruptions ; but in that, as before stated, it is fixed in the bottom of some eruptions, none is produced. It is found also the barrel ; it also can only open upwards. in regions where there are now no active volcanoes,
To describe the action of the pump, we shall as at Andernach on the Rhine.
suppose the piston to be at the bottom of the barrel, PUMPKIN. See GOURD.
and the pump to contain nothing but air. On PUMPS are machines for raising water and moving the piston up the barrel—the valve in it other tluids to a higher level. They are divided being shut, and kept so by the atmospheric pressure into several classes according to their mode of | above it- no air can pass from above it into the
part of the barrel from which it is moving; the air relation between the power expended and the work contained in which becoming rarefied, by having to produced, as measured by the water raised-we occupy a greater space, exerts less pressure on the may remark, that the power is expended--Ist, in valve D at the bottom of the barrel than the air in raising the water through the required height; 2d, suction-pipe B below it. This valve is thus opened, in overcoming the friction of the moving parts
and the air from the suction of the pump; 3d, in the friction and fluid resistance pipe enters the barrel ; so of the water in passing through the valves and pipes; that when the piston has 4th, in the losses arising from the want of proper arrived at the top, a volume proportion between the various parts of the pump. of air equal to the contents The losses arising from these last sources are very of the barrel has passed great, and vary so much according to the con. from the suction-pipe into struction of each particular pump, that no useful the barrel. When the piston estimate can be formed of the efficiency. We may descends, it compresses the say, however, that a pump of this description, to
air in the barrel, which shuts yield 50 per cent. of the applied power, must be C
the valve D; and when the well proportioned and carefully constructed.
the barrel passes to the A
upper side of the piston.
the piston again draws a
like quantity of air from the
by degrees emptied of the
air it contained. During this
the foot of the suction-pipe.
The surface of the water at
and by the laws of fluid.
pressure, if an equal pressure
Fig. 4. of the water in the suction-pipe, the water will rise in it, until the pressu
ssure on its surface, plus the instead of being fixed on the piston, is placed in weight of its fluid column, balances the pressure of the discharge-pipe, the piston itself being solid. the atmosphere on the surface H outside; so that, The water is drawn up into the barrel by suction as the air in the suction-pipe is rarefied, the water in the manner just described in the suction-pipe, rises in it, until, when all the air is extracted from and then the pressure of the piston in its downit, the water stands at the level of the valve D. ward-stroke forces it through the valve E to any By the next upward stroke of the piston, the barrel height that may be required. That shewn in fig. 4 being emptied of air, the water follows the piston, is provided with a different description of piston, and fills the barrel as it filled the suction-pipe. The called the plunger-pole. Its action is precisely the pressure produced by the downward stroke shuts same as that of the other, with this exception, that the valve D, and forces the water in the barrel the plunger-pole, instead of emptying the barrel at through the valve E. The succeeding upward stroke every stroke, merely drives out that quantity which carries this water into the pipe above, and again it displaces by its volume. It is simply a solid rod fills the barrel from the suction-pipe. In like of metal, A, moving through a water-tight stuffing. manner, every successive upward stroke discharges box, B. This stuffing-box is made by placing, on a a body of water equal to the content of the barrel circular flange of metal, rings of india-rubber or into the pipe above it, and the pump will draw other packing, the inner diameter of which is water as long as the action of the piston is con- slightly less than that of the plunger-pole. On tinued.
these is placed a ring of metal, and through the The action of this pump may be more shortly whole are passed bolts, which, on being screwed described by saying that the piston withdraws the tight, force the packing tightly against the plungerair from the barrel, and produces a vacuum, into pole. It possesses many advantages, for the packing which the water rushes through the suction-pipe, can be tightened and repaired without removal of impelled by the pressure of the atmosphere on its the piston or stoppage of the pump; also, the surface. This atmospheric pressure balances a cylinder is not worn by its action, nor does it column of water of about 33 feet in height; so that require to be accurately bored out, as in the other if the barrel be placed at a greater height than this form of pump. from the surface of the water in the well, the water In these pumps, it will be observed that the will not rise into it, and the pump will not draw. water is forced into the ascending pipe or column
With regard to its efficiency--that is to say, the only on the downward stroke; it will thus be
discharged in a series of rushes or jerks. As it is a sense, as a means of producing a given result with
the pressure, and renders box. Fig. 6 shews an example of this pump, which
is worked by a rod B of
piston itself. During the
up-stroke, the upper surface
in twice that volume. In
volumes are sent through
space D, which would other.
wise be left empty by the
descent of the piston; the other volume is sent into the ascending column; so that a volume of water equal to half the content of the barrel is sent into the ascending column by both the up and the down strokes.
A pump exhibited in the International Exhibition of 1862, by Messrs Farcot and Sons, attains this object in a much more simple manner. In it 'two equal pistons, with valves affording very large water-ways, work parallel to each other in two pump cylinders. During the successive strokes, the first piston draws in water by its upper surface, and delivers it to the ascending column by causing it to traverse the second piston. In its ascending course,
T'ig. 6.-Murray's Chain-pump. the second piston raises in its turn the column of water by its upper face, while the lower face sucks the ease of its construction and erection, and its the water, causing it to traverse the first piston.' admirable efficiency even at considerable heights. It will be seen from this description that a valve is In this pump, the friction is reduced by having only placed in each piston, that the cylinders communi. 3 or 4 lifts instead of 20 or 30, as was previously the cate at their base, and that the pistons make their case. The chains pass under a roller, Å, at the foot, strokes simultaneously. This pump has yielded all and are driven by a small pitch-wheel, B, at the top, the good results promised by its ingenious construc-over which they are conducted, and which is driven tion, and it is adopted in the water-supply of by appropriate gearing. The lifts feather in passing Paris.
over the wheel to the descending side, and only In spite of the great antiquity of the lift and unfold when brought round to the ascending side; force pump, it is only of late years that improve. thus the pump is enabled to take off the water with ments have been introduced into its construction the same dip as other pumps. The pump is not capable of rendering it an efficient machine—that is, liable to be choked, as a back turn of the chain one which returns in the shape of water raised, a immediately releases any substance getting between good proportion of the power applied to it. In 1849, the lift and the barrel. The speed is variable, in M. Morin found by experiments that the power lost proportion to the duty required. The speed at was 55 to 82 per cent. —that is to say, that of the which the chain is ordinarily worked is from 200 to motive-power, 45 per cent. was yielded in the best 300 feet per minute. The greatest lift yet made by and 18 in the worst, giving an average of about 30 Murray's chain-pump is 60 feet high ; but it is conper cent.
In 1851, the jury, reporting on those sidered that 100 tons of water per minute could be exbibited in the Great Exhibition, say that it is one raised 100 feet high. From 10 to 12 feet apart has of our worst machines, considered in a mechanical been found to be the best pitch for the lifts ; putting
them nearer, needlessly increases the friction. Expe- leaves the circumference of the wheel, and enters riments made by Mr Lovick for the Metropolitan the circular whirlpool chamber F; so that the Board of Works, shewed that the slip of the lifts interior of the pump may be looked on as a whirlwhich work in the barrel, and are one-eighth of an pool, extending from the axle of the wheel to the inch shorter each way than the barrel, averaged 20 circumference of the whirlpool chamber. Into this per cent. of their motion, and that the useful work whirlpool the water is drawn at the central orifice done averaged 63 per cent. of the indicator horse of the wheel, and discharged by the pipe G at the power of the engine working it.
circumference of the whirlpool chamber; and the 4. The Centrifugal Pump.—These pumps, with force with which it is discharged, or the height to reference to those previously described, may be which it will rise in the pipe G, is measured by the called new, as, though they have been in use in one centrifugal force of the water revolving in the form or another for at least a century, their merits whirlpool. were not brought prominently forward till the year With reference to the efficiency of these pumps, 1851, when the great efficiency of the models it is impossible to give any accurate estimate, since exhibited by Messrs Appold, Gwynne, and Bessemer as high as 70 per cent of the applied power is drew general attention to the subject.
claimed to be returned by forms of the pump shewn The essential parts of this pump are-1. The in figs. 7 and 8, while some other descriptions expewheel to which the water is admitted at the axis, rimented on in 1851 gave only 18 per cent. of useful and from which it is expelled at the circumference, effect. by the centrifugal force due to the rotatory motion It will be evident, from the above description imparted to it in passing through the rapidly re- of the pump, that the height to which the water volving wheel; and 2. The casing or box in which will be raised depends entirely upon the speed of the wheel works, and by which the entering water revolution of the wheel ; and it is by this that the is separated from that discharged.
application of centrifugal pumps is limited to comFigs. 7 and 8 are a section and plan of a cen- paratively low lifts of say less than 20 feet, as the trifugal pump. The water enters the pump by the speed for high lifts requires to be greater than can
be conveniently and usefully attained in practice. They are best applied when raising large quantities of water through low lifts. It will also be observed, that on account of the simplicity of their parts, and the absence of valves, they are much less liable than other pumps to be choked by the entrance of solid materials. In some descriptions of this pump, the exterior whirlpool chamber is dispensed with ; and to the vanes of the wheel is given such a curvature backwards from the direction of motion, that the water leaving the circumference of the wheel is
spouted backwards from the vane-passages with a A
speed equal to that of the wheel in the opposite direction, so that it has only a radial motion with reference to a fixed object; in other words, that the force is acquired from the radial component of the pressure of the vanes, instead of the centrifugal force of the revolving water. Those pumps, how
ever, give the best results which, as the one above Fig. 7.
described, combine both actions.
curved vanes are much superior to straight ones. supply-pipes A, A, which lead to the central orifices 5. The Jet-pump.—This pump is worked by of the wheel B, B; it then passes through the pass- water-power, and is worthy of notice on account of ages C, C, formed by the vanes and the side cover the extreme simplicity of its parts, and of not ing-plates, D, of the wheel. In passing through requiring the care of an attendant while in opera
Fig. 9 is a representation of this pump, C is the water which it is required to raise to the level of the water D, and B is the water in the stream available for working the pump.
The water B passes down the pipe A, and is discharged from the jet or nozzle, E, into the conical pipe F. Round the nozzle is the vacuum-chamber G, at the bottom of which is attached the conical pipe F, and into the side of which the suction-pipe H enters from the water to be pumped. The water, in passing from the nozzle into the conical pipe, carries air with it, and so gradually forms a vacuum in the chamber G, when the water rises into it from the level C, through the pipe H; and it is in turn carried with the jet down the conical pipe into the dischargelevel D. The velocity of the water coming from the jet is gradually retarded by the action of the conical pipe, the speed decreasing as the area of section
increases; and the vis viva of its motion is by this Fig. 8. -Thonison's Centrifugal Pump. retardation converted into a sucking force, drawing
the water from the suction-pipe through the vacuum these passages of the wheel, which is made to chamber into the conical pipe. The water issuing revolve by power applied to the shaft E, it acquires from the jet will have a speed equal to that proa rotatory motion, which still continues when it duced by a column of the height BC, or the sum of
the fall and lift. This pump may be viewed, for name of a witty buffoon of Acerra who joined a purposes of explanation, as a syplon, into the company of players and became the favourite of the shorter leg of which a jet of water is injected, Neapolitan populace. Others give his original name
as Paolo Cinella. The variety and inconsistency of the legends shew them to be myths-histories invented to account for the name. The modern P. is only a modification of an ancient Mask (q. v.) to be seen represented on ancient vases, and taken perhaps from the Oscan Atellanæ ; and the Italian name is pretty evidently a diminutive of pollice, the thumb_Tom Thumb (the dwarfs of northern mythology are sometimes styled däumling, thumkins). The English name Punch is apparently identical with Eng. paunch ; Bavarian punzen, a cask; Ital. punzone, a puncheon; and denotes any. thing thick and short (e. g., a Suffolk punch). The name Punchinello seems to have arisen from blending the English and Italian names.
The drama or play in which the modern P. figures, is ascribed to an Italian comedian, Silvio Fiorillo, about 1600. The exhibition soon found its way into other countries, and was very popular in England in the 17th century. Its popularity seems to have reached its height in the time of Queen Anne, and Addison has given in the Spectator a regular criticism of one of the performances. The scenes as now given by the itinerant exhibiters of the piece are much shortened from what were originally performed, in which allusions to public events of the time were occasionally interpolated. The fol
lowing is an outline of the plot as performed Fig. 9.
in 1813. Mr P., a gentleman of great personal
attraction, is married to Mrs Judy, by whom he which overcomes the pressure due to the difference has a lovely daughter, but to whom no name is of levels, and reverses the ordinary motion of the given in this piece, the infant being too young to water in a syphon. An efficiency of 18 per cent. has be christened. In a fit of horrid and demoniac been obtained from this pump, which is low, as jealousy, P., like a second Zeluco, strangles his compared with that obtained from other descrip- beauteous offspring. Just as he has completed his tions of pump; yet in cases where waste of water- dreadful purpose, Mrs Judy enters, witnesses the power is not so much to be avoided as expense in brutal havoc, and exit screaming; she soon returns, erecting, working, and maintenance, these pumps however, armed with a bludgeon, and applies it to possess decided advantages. The case to which her husband's head, 'which to the wood returns a they are peculiarly applicable is the drainage of wooden sound.' P. at length exasperated seizes marshes, which have streams of water adjacent to another bludgeon, soon vanquishes his alreadythem descending from a higher level.
weakened foe, and lays her prostrate at his PUN is the name given to a play upon words. expiring mother, he fings them both out of the
feet; then seizing the murdered infant and the The wit lies in the equivocal sense of some parti. window into the street. The dead bodies having cular expression, by means of which an incongruous, and therefore ludicrous idea is unexpectedly P., who flies for his life, mounts his steed;
been found, police officers enter the dwelling of shot into the sentence. One or two examples will make the matter clearer than any detinition. Two the confining unities of time and place, conveys
and the author neglecting, like other great poets, persons looking at a beggar.boy with an extraordi- his hero into Spain, where, however, he is arrested nary big head What a tower !' cried the first. lice" (fortalice). --A noted punster was once asked, fortitude, P., by means of a golden key, opens his Say, rather,” replied the second, "what a fort o by an officer of the terrible Inquisition. After
enduring the most cruel tortures with incredible with reference to Mr Carlyle's writings, if he did
The conclusion of the not like to expatinte in such a field.'•.No,' was story is satirical, allegorical
, and poetical. The hero
prison-door, and escapes. the felicitous rejoinder ; ' I can't get over the style' is first overtaken by Weariness and Laziness in the (stile).—A Massachusetts lady complaining to a friend that her husband (whose business haŭ taken shape of a black dog, which he fights and conquers ; him to the far West) constantly sent her letters him ; but P. sees through the thin pretence," and
Disease, in the disguise of a physician, next arrests filled with expressions of endearment, but no money, dismisses the doctor with a few derogatory kicks. was told, by way of comfort, that he was giving her Death at length visits the fugitive; but P. lays a proof of his unremitting affection!
about his skeleton carcass so lustily, and makes PUNCH, the chief character in a popular comic the bones of his antagonist rattle so musically with exhibition performed by means of Puppets (q. v.). a bastinado, that “Death his death's blow then Various accounts are given of the origin of the received.' Last of all comes the Devil ; first under name. The exhibition is of Italian origin, and the the appearance of a lovely female, but afterwards Italian name is Pulcinella, or Policinella. Accord in his own natural shape, to drag the offender to ing to one story, a peasant, a well-known character the infernal regions, to expiate his dreadful crimes. in the market-place of Naples, got the name Even this attempt fails, and P. is left triumPulcinella from dealing in fowls (pulcinelli), and phant over Doctors, Death, and the Devil. The after his death was personated in the puppet-shows curtain falls amid the shouts of the conqueror, who, of the San-Carlino theatre. Another account makes on his victorious staff, lifts on high his vanquished the word a corruption of Puccio d'Aniello, the foe.