pressure by the finger. Hardness is favored by a powerfully acting heart, a normal amount of blood, and contraction of the peripheral blood vessels, as for instance by cold. Softness of the pulse is favored by a feeble heart, by valvular imperfections interfering with the supply of blood to the arterial system, and by a free flow through the capillary area. A hard pulse is generally indicative of inflammation, and a soft or compressible pulse of general weakness.

The blood from the veins returns to the heart

under normal conditions in a steady stream, the pulse being lost in the capillary area. Some pulsation, however, can often be seen in the larger veins near the heart, the jugular veins, for example, in many persons with a healthy circulation. The expansion of the vein is synchronous with dilatation of the ventricles, and collapse with contraction. Another kind of pulsation, in which this relation is reversed, takes place when the tricuspid valves guarding the veins become insufficient through disease. A wave of blood is sent back into the venous trunks, producing a visible pulsation. This phenomenon may also be produced by hypertrophy of the right auricle and aneurism of the aorta..

An instrument has been devised by which the variations of the pulse can be indicated upon paper attached to a revolving cylinder. See SPHYGMOGRAPH; HEART, DISEASES OF THE; ARTERIES, paragraph Diseases.

PULSOMETER. See PUMPS AND PUMPING

MACHINERY.

PULSZKY, pulske, FRANZ AUREL (1814-97). An Hungarian politician and author, born in Eperies. He studied law, and visited England, where he wrote in German and Hungarian Aus dem Tagebuche eines in Grossbritannien reisenden Ungarn (1837). In 1839, he entered the Diet as member from Sáros. In 1848 he became Under-Secretary of State in the Hungarian Ministry of Finance, and subsequently Minister of Commerce. After Kossuth went to England, Pulszky remained with him, and accompanied him on his journey through America, described in White, Red, and Black (1852) in English. He was condemned to death in contumaciam by the Austrian Government in 1852. After 1860 Pulszky resided in Italy. He fought under Garibaldi. In 1866 he was pardoned. After his return to Hungary he was elected to the Diet and became director of the National Museum at Pesth. His publications include: Die Jakobiner in Ungarn (1851), a romance; Eletem és Korom (1882), an autobiography; and Die Kupferzeit in Ungarn (1884).

PULTENEY, pult'nê, WILLIAM, Earl of Bath (1684-1764). An English political leader, born in London. He was educated at Westminster School and Christ Church, Oxford, and after traveling on the Continent, entered Parliament as a Whig in 1705. On the prosecution of Walpole in 1712, he defended him with great eloquence, and from 1714 to 1717 was his Secretary of War. In 1725, however, he joined the opposition, and became the bitter antagonist of his former friend, succeeding by the brilliancy of his speeches in depriving him of his place. Shortly after Walpole's fall in 1742 Pulteney I was created Earl of Bath. On the resignation of the Pelham Ministry in 1746 he was made Premier, but, unable to form a Cabinet, he held

the office for only two days and then practically retired from public life. As a speaker, Pulteney was full of spirit and fire and showed much of the searching keenness of satire, the inexhaustible resources of ridicule and persiflage, which distinguished him as a writer. He joined Bolingbroke in establishing The Craftsman (1726), a political periodical, and he wrote many political pamphlets and verses, including the popular song The Honest Jury, or Caleb Triumphant.

city of Russia. See POLTAVA. PULTOWA, pul-to'vå. A government and a

PULTUSK, pul'tusk. A town of Russian Poland, in the Government of Warsaw, situated on the Narev about 34 miles north of Warsaw (Map: Russia, B 4). It is a well-built town with an old castle, the former It is noted residence of the bishops of Plotzk. as the scene of an engagement between the Russians and the French in 1806. Population, in 1897, 15,900.

out.

PUMA (Peruvian name), COUGAR, or MOUNTAIN LION. A large American cat (Felis concolor) originally native from the watershed of Hudson Bay to the Straits of Magellan, and still present except in the most civilized parts of the country. It is of slender build, with a rather small head and long limbs, and usually measures about 40 inches from the snout to the root of the tail, which usually is about 26 inches in length, and of nearly the same thickness throughUnlike the other great American cat, the jaguar (q.v.), which is densely spotted, the adult puma has no spots, except that the lips and the outer rim of the ear are black, there is a patch of white on each side of the muzzle, and the tip of the tail usually is blackish. The upper parts are uniform dull fox-red, appearing gray in certain lights, owing to the fact that each hair is fawn-gray, red only at the tip; the throat, belly, and inside of the legs are reddish-white. unspotted, tawny coat led the earliest explorers on the Atlantic coast to regard the animal as a lion, and the name survives in the West. early settlers in the States called it a panther (usually pronounced 'painter'). 'Cougar' is derived from a Brazilian language, but involves an error. (See COUGAR.) 'Puma' was its native name in Peru. Considering that the species is distributed over so great a range of territory, its variations in form and color are surprisingly small.

This

The

In the Eastern United States it has been greatly dreaded as a fierce and treacherous beast, particularly dangerous because of its alleged habit of springing upon travelers from branches of trees or rocky ledges. When attacked it was courageous in resistance, and the killing of one was justly considered evidence of skill and courage. In the West, on the other hand, the mountain lion, although more numerous in the Rocky Mountains than the panther ever appears to have been in the East, has always been regarded as a shy and cowardly beast, little to be feared, except when cornered. The truth seems to be that this animal has less ferocity than any other of the great cats, and under ordinary circumstances is inclined to avoid rather than to attack men, and often seems to seek their company in a friendly way. This timidity and confidence aided the easy extinction of these animals throughout the eastern part of the country, but they are still

abundant in the Rocky Mountains, and westward, where the ranching industries supply them with abundant food in the young cattle and horses. The principal food of the puma in North America was deer, but it seized any smaller prey which came in its way. The mode of hunting was by lying in wait for or creeping within leaping distance of the victim and then springing upon it. In the case of sheep, to which in the Southwestern United States it is especially destructive, the puma rarely contents itself with taking a single one, which would satisfy its hunger, but, having once entered a fold or flock, it kills right and left, so that in many cases a hundred sheep have been killed out of a flock in one night by a single puma. Their silence when hunting or when attacked is a notable characteristic; yet on rare occasions, in winter nights, they make the woods resound with terrifying screams. The young are born in the early spring, and are usually two or three in number; and it is believed that under natural conditions most pairs breed only once in two years. The kittens at first are covered with black spots and stripes, and their tails are ringed. These markings disappear at the end of about six months, after which they become of the uniform color of their parents. Full size is not attained before the end of the second year, and during all this time they associate with the mother, while the father of the family seems to lead a solitary existence. Like other cats, their hunting is entirely at night.

BIBLIOGRAPHY. True, "The Puma," an illustrated monograph with full bibliography, in Annual Report Smithsonian Institution (Washington, 1889); Merriam, Vertebrates of the Adirondacks (New York, 1893); Porter, Wild Beasts (New York, 1894); Baillie-Grohman, Fifteen Years in the Hunting Grounds of Western America (London, 1900); Alston, Biologia Centrali-Americana (London, 1879-82); Hudson, The Naturalist in La Plata (London, 1892). See Colored Plate of CAT FAMILY, accompanying article LION.

PUMBLECHOOK, pùm'b'l-chook, MR. Uncle to Joe Gargery in Dickens's Great Expectations, a fishy-eyed, pompous man, who bullied Pip when he was poor, but was most servile when he came into his money.

PUMELO. See GRAPEFRUIT.

PUMICE (from Lat. pumex; probably connected with spuma, foam). An effusive igneous rock, having a spongy or frothy texture, and composed largely or entirely of glass. It is frequently made up of parallel fibres or threads with intervening spaces to form a delicate structure. It is produced by the expansion of the occluded moisture of lavas when they reach the surface of the earth, and is most abundantly developed in lavas of rhyolitic composition (see RHYOLITE), since these are usually very viscous. It may, however, be exceptionally produced in connection with any effusive rock, and is hence classified in respect to its chemical composition into rhyolite pumice, trachyte pumice, and the like. Pumice is extensively used in the manufacture of tooth powder and other abrasive materials. Most of the commercial product is derived from the Lipari Islands.

PUMP. See PUMPS AND PUMPING MACHINERY. PUMPEL'LY, RAPHAEL (1837-). An American geologist, born in Owego, N. Y., and

educated in Hanover, Germany, and in the mining schools of Paris and Freiberg, from 1854 to 1860. After explorations in Corsica and in Arizona, he received in 1861 a commission from the Japanese Government to explore the mineral wealth of the island of Yesso. In February, 1863, under pressure of the anti-foreign party, the Shogun dismissed the foreign employees who were "spying out the land." Pumpelly then went to China, and, having been commissioned by the Chinese Government to report on the coal supply of the Empire, he made journeys through the central and northern provinces and into the Desert of Gobi. Upon the completion of this work in 1864, he spent a short time in Nagasaki, and then returned to Europe by way of Siberia. The Smithsonian Institution published a volume recording his geological researches in China, Mongolia, and Japan, and this was supplemented by a popular narrative of his travels and adventures entitled Across America and Asia (1870). Upon his return to the United States Pumpelly was appointed professor of mining in Harvard University, an office which he held from 1866 to 1873. During a short period he was the State geologist of Michigan and then of Missouri, and in 1879 he entered the service of the United States Geological Survey. In 1879-80, he conducted at Newport, R. I., an investigation for the National Board of Health on the filtering ability of various soils. In 1881 he organized an important transcontinental survey through the northwestern territories of the United States. In 1884 he again entered the United States Geological Survey. In 1903 he left this country for the purpose of mak ing observations in the Trans-Caspian country under the auspices of the Carnegie Institution of Washington. His publications include: Geolog ical Researches in China, Mongolia, and Japan, published by the Smithsonian Institution (1866); Across America and Asia (1870); Geology of the Copper District of Michigan (1875); Iron Ores and Coal Fields in Missouri (1873); "The Mining Industries of the United States," in vol. xv. of the United States Census Report (1886); and Geology of the Green Mountains (1894).

PUMPKIN (variant of pumpion, from OF. pompom, variant of pepon, from Lat. pepo, from Gk. Téπwν, реpōn, kind of melon, ripe; connected with Skt. pakva, ripe, from pac, to cook; influenced by popular etymology with the Eng. diminutive termination -kin). The common name of several annual, vine-like, tendril-bearing herbs of the genus Cucurbita, family Cucurbitaceæ, natives of warm countries, cultivated for their fruits. The common field pumpkin (Cucurbita Pepo) is a coarse running, rough-leaved vine, often exceeding 20 feet in length. The fruit is gourdlike, oblong with flattened ends, yellow when ripe, and normally weighing from 15 to 40 pounds. The edible portion consists of a fleshy layer an inch or more thick beneath the rind. In America the pumpkin is extensively planted in cornfields in occasional hills of corn. In its raw state the fruit is used as a cattle food, and, after having its hard outer rind and seeds removed, for making pies. The method of cultivation are the same as for squash (q.v.). See Plate of CUCUMBER ALLIES.

PUMPKIN INSECTS. See SQUASH INSECTS. PUMPKINSEED. See SUNFISH.

PUMPS AND PUMPING MACHINERY (OF., Fr. pompe, Ger. Pumpe, Plumpe, Plumpfe; possibly, though very doubtfully, connected with Lat. plumbum, lead). Devices used to move liquids and gases. The various kinds of pumps, without regard to their motive power, may be broadly classified as follows: (1) Bucket lifts, or water elevators, by means of which a balanced pole, or sweep, a windlass, or a wheel, lowers, raises, and empties one or more buckets or other receptacles. (2) Displacement pumps, acting on the principle that two bodies cannot occupy the same space at the same time. (3) Impellers, which by their own continuous motion in the water to be moved impart some of their velocity to water with which they come in contact. (4) Impulse pumps, which employ the force of a suddenly arrested large column of water to lift a smaller column to a greater elevation than the original source. See HYDRAULIC RAM.

These

BUCKET LIFTS, or WATER ELEVATORS. are the simplest of the four classes of pumps named. They have been used from the remotest historical times and are still employed in varying forms the world over. The well sweep, or bucket and balanced pole, still frequently seen in certain rural sections of America, is much the same as the shadoof of Egypt and the paecottah of India. The single bucket or, in Oriental countries, the earthen pot, attached to a rope, wound around a windlass, is another very common water lift. A series of buckets mounted on an endless rope or chain, dipping into the water below, and running over and driven by a wheel above, is an improvement over either of the foregoing, giving a continuous stream of water. Primitive multiple bucket or pot lifts of this general character, driven by animal power acting through a rude combination of wheels and horizontal sweeps, are sometimes known as Persian wheels. Modern refinements of this device are called chain pumps. Sometimes the wheel carrying the buckets is placed in and driven by a running stream. Another form of water lift is the scoop wheel, composed of a series of curved blades, terminating in a hollow axle, into which they discharge the water scooped up by the revolution of the wheel. Where similarly arranged curved tubes take the place of the blades the device is called a tympanum. Of the various water lifts described the bucket and chain pumps are most extensively used, particularly where manual labor is costly.

DISPLACEMENT PUMPS. In their most common form they employ a piston to push water ahead of them in a cylinder which the piston tightly fits, or else a plunger which does not wholly fill the cylinder, instead of forcing all the water in the cylinder ahead of it, merely displaces a volume equal to that of the plunger itself. Instead of a piston, steam or air may be used to effect the displacement. Valves are an essential feature of displacement pumps, and may also be used on the outlet end of impeller or centrifugal and jet pumps, to prevent back pressure when the pumps are not running. In the simplest form, as in the ordinary suction lift pump, described below, valves are nothing more than pieces of leather or rubber, cut to the desired shape, and hinged at one edge or side. They lift for the passage of the water upward and close on the reverse stroke of the piston in order to prevent a reverse flow. In most large pumps

well pumps. The Reidler valve, a German device used on some of the highest grades of American and foreign pumps, employs only one valve on each inlet or outlet, which is closed mechanically, instead of by the force of the liquid being pumped, and therefore has a positive and comparatively gentle motion, combined with a single large waterway of ample capacity. Valve stems control the lift of the valves and prevent displacement from their seats, while the springs are designed to take up slacks. When the only function of a valve is to prevent back pressure, or flow, a single check or flap valve may be used.

Displacement pumps are subdivided into many classes, of which the following are the most important: Reciprocating pumps have either pistons or plungers which move alternately back and forth or up and down, always in a straight line. Such pumps are single or double acting, according to whether the water is displaced on one or both parts of the stroke. They are also known as direct-acting when the motive power is applied in a direct line with the movement of the piston or plunger, and as of the crank-and-fly-wheel type, or the beam type, when either of these devices is employed to transmit the motion. The beam is similar to the walking-beam of some steamboats and is an essential feature of the old Cornish beam engine. (See STEAM ENGINES.) Pumps are known as simple, duplex, triple, etc., according as one, two, or more pistons or plungers are driven by a motive power unit. Beam pumps are rapidly diminishing in relative numbers. Crank-and-fly-wheel pumps are quite extensively used, particularly for high duties and for power pumps. Direct-acting pumps are very common. While large numbers of simple pumps are in use, duplex and triple, but more particularly du

plex, are the rule, except for small sizes and special purposes. Rotary pumps have revolving instead of reciprocating pistons. Two pistons revolve on parallel axes. Their longitudinal surfaces are formed into a series of curves, so they mesh closely on the inside as they revolve, while their outer parts fit tightly against a curved pump chamber. Screw pumps displace water when revolved in a chamber with proper inlets and outlets. Chain piston pumps are a simple type, consisting of a series of pistons mounted on an endless chain. Both pistons and chain pass upward through a vertical cylinder, forcing water ahead of them, then descending again to repeat the process. The Pulsometer is a more elaborate apparatus, in which the pump and motive power are combined. The displacement is effected by means of steam, acting in two connecting chambers. On admitting steam into one of these the water is forced out gradually, but with the increasing wall area to which the steam is exposed with the expulsion of the water the steam is condensed, a vacuum is created, more water rushes in, and the steam is automatically turned into the other chamber, whereupon the process is repeated. Such pumps are very largely used by contractors and others for pumping dirty water, or even water containing mud and small stones, on account of their comparatively simple construction and great durability.

The work done by a pump, when the pump is placed above the level of the water to be raised, and at the same time below its final elevation, is frequently classified as suction-lift for the first part, and force-lift for raising the water above the pump level. Pumps may perform either suction or force lift alone, or the two combined, according to their location.

The accompanying diagram represents the ordinary suction pump. A is a cylinder, which is called the barrel; with it is connected at the bottom a pipe, B, which communicates with the water to be raised; and at its top is another pipe, C, which receives the water raised. In the barrel are placed two valves, D and E. D opens upward and is fixed in position at the bottom of the barrel; E also opens upward and is attached to and forms part of the piston F, which moves up and down the barrel when motive power is applied to the rod G. When the valve E is opened, water or air can pass through it to the upper side of the piston; but when shut, none can pass from one side of the piston to the other. The other valve, D, is similar to it in all respects. On moving the piston up the barrel, the valve E closes, owing to the atmosphere pressure above it; no air can pass from above it into the part of the barrel from which it is moving. The air contained in the lower part of the barrel becomes rarefied, by having to occupy a greater space, and exerts less pressure on the valve D at the bottom of the barrel than the air in suction pipe B below it. This valve is thus opened, and the air from the suction pipe enters the barrel; so that when the piston has arrived at the top, a volume of air equal to the contents of the barrel has passed from the suction pipe into the barrel. When the piston descends, it compresses the air in the barrel, which shuts the valve D; and when the density of the compressed air becomes greater than that of the atmosphere, the valve E in the piston is forced open, and the air in the barrel passes to the upper side of the piston. The next upward

stroke of the piston again draws a like quantity of air from the suction pipe into the barrel; and, as none of this air again enters the pipe, but is passed to the upper side of the piston by its downward stroke, the suction pipe is by degrees emptied of the air it contained. During this process, however, motion has taken place in the water water at H is pressed upon by the weight of the at the foot of the suction pipe. The surface of the atmosphere with a pressure of about 15 pounds pressure, if an equal pressure is not exerted on on every square inch; and, by the laws of fluid the surface of the water in the suction pipe, the water will rise in it, until the pressure on the sur

FE

D

B

face, plus the weight of its fluid column, balances the pressure of the atmosphere on the surface H outside; so that, as the air in the suction pipe is rarefied, the water rises in it, until, when all the air is extracted from it, the water stands at the level of the valve D. By the next upward stroke of the piston, the barrel being emptied of air, the water follows the pisbarrel as it filled ton, and fills the the suction pipe. The pressure produced by the downward stroke shuts the valve D, and forces the water in the barrel through the valve E. The succeeding upward stroke carries this water into the pipe above, and again fills the barrel from the suction pipe. In like manner, every successive upward stroke discharges a body of water equal to the content of the barrel into the pipe above it, and the pump will draw water as long as the action of the piston is continued.

H

SINGLE SUCTION PUMP.

The ordinary forms of lift and force pumps are very similar to the suction-lift pump before described, with this exception, that the valve represented by E, instead of being fixed on the piston, is placed in the discharge pipe, the piston itself being solid. The water is drawn up into the barrel by suction in the manner just described in the suction pipe, and then the pressure of the piston in its downward stroke forces it through the outlet valve to any height that may be required.

In these pumps it will be observed that the water is forced into the ascending pipe or column only on the downward stroke; it will thus be discharged in a series of rushes or jerks. As it is a great object to procure a continuous discharge, both for its convenience, and for the saving of

the power wasted by the continual acceleration and retardation of the ascending column, various methods have been used for that purpose. The most common is the air chamber, which is an airtight receptacle fixed vertically on the discharge pipe; the water forced into the pipe by the down stroke compresses this air, which, acting as a spring, returns this force to the ascending column during the period of the up stroke, and so, by taking the blow of the entering water, and returning it gradually, equalizes the pressure, and renders the discharge uniform.

If in place of a piston, which fits the pump cylinder tightly, a plunger rod smaller than the cylinder be used, working in a water-tight packing or stuffing box and discharging through an outward opening valve at the other end, we have a simple force pump, which may at the same time be made very powerful. It will be understood that the pistons or plungers may work in either a horizontal or vertical direction, giving rise to the terms horizontal and vertical pumps, and that, as already mentioned under valves, most of the large displacement pumps have a number of small inlet and outlet valves, instead of one large one.

connecting it by means of a long piston, or pump rods with some sort of motive power at the surface. Air-lift pumps are cheap in first construction, simple in operation, and have no wearing parts, but their fuel economy is low. As steam lifts thousands of times more water than any other artificial agent, the term pumping engine, and even the word pump alone, is often employed to denote the combination of a pump and a steam engine in one machine; while when a pump is driven by detached motive power, even if that power be steam itself, the pump is termed a power pump-that is, one operated by independent power. There is a tendency to confine the term 'pumping engine' to more or less elaborate machines of large capacity, and to confine the use of the term 'steam pumps' to those of smaller capacity and simpler design, but there is no hard and fast line between the two. Other motive powers for pumps are electricity, gas, gasoline, and oil engines. With the exception of the steam pumping engine, the various motors employed to drive pumps will not be described further in this article, and most of the principles involved in the steam end of pumping engine will be explained under STEAM ENGINE.

Air Chamber

Pump Discharge

Link Movement

Cap

Rod

Head

machine into a screw Cylinder pump, with displacement due to pressure. Centrifugal pumps are generally confined to raising water to comparatively small elevations, but they may be employed for higher lifts, although not so economically

a

as some form of displacement pump. Jet pumps make use of a jet of steam or water, which, being delivered at high velocity through a small throat imparts some of its velocity to the water to be moved. The air lift has been classed by some as a displacement, and by others as jet pump. It seems more correct to say that its action depends upon the formation of a column of water and air, which, because of its lesser specific gravity or weight, is overbalanced, or raised, by a column of water. Two tubes are employed, the smaller of which is centered within the larger. The small inner pipe conveys compressed air down into the volume of water to be lifted. The air and water together rise up through the outer and larger tube. This device is used oftentimes as a substitute for deep-well reciprocating piston pumps, which require the placing of a pump deep in the well and

-Water
Cylinder
Head

-Water
Piston
Follower

Pump Inlet

STEAM PUMPING ENGINES. The simplest of these machines consists of a single steam and a a single water cylinder, with a common piston, but this type did not come into use until ponderous beam engines had been employed for scores of years. All steam pumping engines have pumps of the displacement type. The steam end of the pump may use the steam at its initial pressure through the whole length of the stroke, when it falls in the simple, high-pressure type. If now the steam, after having done all possible work in the first cylinder, is admitted to a second one, still further service may be secured and the machine becomes compound. A third, or even a fourth cylinder may be used, in which case the terms triple and quadruple expansion are employed. If it is desirable to obtain still higher degrees of expansion, cut-offs are employed, so the steam is shut off when the stroke of the pis