Page:EB1911 - Volume 21.djvu/904

Rh blood vessels. Later the lung becomes converted into a series of bronchiectatic cavities This condition is usually present to a greater or less degree in almost all chronic diseases of the lungs and bronchi, but it is specially apt to arise in an extensive form from pre-existing catarrhal pneumonia, and not infrequently occurs in connexion with occupations which necessitate the habitual inhalation of particles of dust, such as those of colliers, flax-dressers, stonemasons, millers, &c., to which the term pneumonokoniosis is now applied (including anthracosis, siderosis, chalicosis and the so-called “grinder’s rot”).

The symptoms are very similar to those of chronic phthisis (see ), especially increasing difficulty of breathing, particularly on exertion, cough either dry or with expectoration, sometimes copious and fetid. In the case of coal-miners the sputum is black from containing carbonaceous matter. The physical signs are deficient expansion of the affected side—the disease being mostly confined to one lung—increasing dullness on percussion, tubular breathing and moist sounds. As the disease progresses retraction of the side becomes manifest, and the heart and liver may be displaced. Ultimately the condition, both as regards physical signs and symptoms, takes the characters of the later stages of pulmonary phthisis with colliquative symptoms, increasing emaciation and death. Occasionally dropsy is present from the heart becoming affected in the course of the disease. The malady is usually of long duration, many cases remaining for years in a stationary condition and even undergoing temporary improvement in mild weather, but the tendency is on the whole downward.

See Allbutt and Rolleston, System of Medicine (1909); R. W. Allen, Vaccine Therapy and the Opsonic Method of Treatment (1908); Osler, Practice of Medicine (1909); The Practitioner (May 1908); Clinical Journal (Jan. 1908); American Journal of the Medical Sciences (Jan. 1908); W. C. Bosanquet and J. Eyre, Serums, Vaccines and Toxines (1909).

 PNOM-PENH, a town of French Indo-China, capital, since 1866, of the protectorate of Cambodia and seat of the resident superior. Pop. about 60,000, consisting of Cambodians, Annamese, Chinese, Malays, Indians and about 600 Europeans. It is situated on the Mekong about 173 m. from its mouth at the point where it divides into two arms and is joined by the branch connecting it with the Great Lake (Tonlé Sap). Its position makes it the market for the products of Cambodia, Laos, Upper Burma and part of Siam (dried fish, rice, cotton, indigo, cardamoms, &c.) The town is lighted by electricity. The palace of the king of Cambodia occupies a large space in the Cambodian quarter. The town gets its name from the Pnôm, a central hill surmounted by an ancient pagoda.

 PO (anc. Padus, Gr.  ), a river of northern Italy, and the largest in the whole country, with a total length of about 310 m. direct from the source to the mouth, but, including its many windings, of some 417 m. The navigable portion from Casale Monferrato to the mouth is 337 m., the minimum width of this portion 656 ft., and its minimum depth 7 ft. Owing to the prevalence of shallows and sandbanks, navigation is difficult.

The Po is the dominating factor in north Italian geography, north Italy practically consisting of the Po basin, with the surrounding slopes of the Alps and Apennines. For a description of its course, and a list of its principal tributaries see. The area of its basin, which includes portions of Switzerland and Austria, is estimated at 26,798 sq. m.

In the first 21 m. of its course, down to Revello (west of Saluzzo), the Po descends no less than 5250 ft., or a fall of 47.3 : 1000, forming a very remarkable contrast to its fall lower down. From the confluence of the Ticino its fall is about 0.3 : 1000; from the beginning of the delta below Ferrara, 0.08 : 1000. At Turin it has an average width of 400 to 415 ft., a mean depth of 3 to 5 ft., and a velocity of 1 to 3 ft. in the second. The mean depth from the confluence of the Ticino (altitude 217 ft.) downwards is 6 to 15 ft. The river is embanked from Piacenza, and continuously from Cremona, the total length of the embankments exceeding 600 m. Owing to its confinement between these high banks, and to the great amount of sedimentary matter which the river brings down with it, its bed has been gradually raised, so that in its lower course it is in many places above the level of the surrounding country. A result of confining the stream between its containing banks is the rapid growth of the delta. Lombardini calculated that the annual increase in the area of the Po delta during the period 1300 to 1600 amounted to 127 acres; but during the period 1600 to 1830 it rose to 324 acres. Marinelli estimated that between the years 1823

and 1893 the annual increase was at the average rate of 173 to 175 acres, and the total accretion at about 20 sq. m.; and the total area of inundated land north and south of the delta at nearly 60 sq. m. He further estimated that the Po della Maestra advances 282 ft. annually, the Po delle Tolle 262 ft., the Po della Gnocca 111 ft., and the Po di Goro 259 ft. The low ground between the lower Po and the lower Adige and the sea is known as Polesine, a name the derivation of which is much discussed. It is generally applied only to the province of Rovigo, but is sometimes extended to the neighbourhood of Adria and Ferrara. All along its course from Chivasso (below Turin) down to the delta the river is connected with several of its tributaries by canals, and at the same time other canals connect the tributaries and carry off their waters and the waters of the Po purely for purposes of irrigation.

The researches of Helbig (Die Italiker in der Po-Ebene, Leipzig, 1879) show that the lower valley of the Po was at an early period occupied by people of the Palaeolithic and Neolithic stages of civilization, who built houses on piles along the swampy borders of the streams. It is possible that even they may have begun by crude dikes the great system by which the waters are now controlled; at least it is certain that these works date their origin from pre-Roman antiquity. Pliny refers them to the Etruscans. The reclaiming and protecting of the riparian lands went on rapidly under the Romans, and in several places the rectangular divisions of the ground, still remarkably distinct, show the military character of some of the agricultural colonies. During the time of the barbarian invasions much of the protective system was allowed to fall into decay; but the latter part of the middle ages saw the works resumed with great energy, so that the main features of the present arrangement were in existence by the close of the 15th century.

The earlier Roman writers speak of the region between the northern boundaries of Etruria and Umbria and the Alps as Gallia Cisalpina. It was separate from Italy proper, the Aesis first and then the Rubicon being the boundary on the east, and the Arnus the boundary on the west, so that, for example, Luca remained outside the boundaries of Italy proper, even in 89 Romanization had, however, progressed considerable, the foundation of colonies and the construction of roads had, gone on during the 2nd century, and the whole district as far as the Padus was given the Roman franchise in 89, while the Transpadanes received Latin rights, and were fully enfranchised forty years later. Cisalpine Gaul was apparently formed into a province by Sulla in 81 and continued to be so until the fall of the Republic.

The Ligurian name of the Po was Bodincus or Bodencus, i.e. the bottomless. The name Padus was taken from the Celts or the Veneti. Thus we find Bodincomagus as a town name (Industria) on the upper course, and (Padua, Catull. 95, 7) as a name of one of the mouths of the river. The name (Eridanus) of Greek poetry was identified with it at a comparatively late period.

 POACH (probably from Fr. poche, bag, or Eng. “poke,” thrust into), to trespass on private property in pursuit of game or fish; also, generally, to catch game or fish by means or at times not permitted by the law, or in an unsportsmanlike manner (see ). The etymology is rather obscure, but as used in the independent sense of “poaching” an egg, i.e. cooking by breaking into boiling water, the word appears to be from the same original.

 POBÊDONOSTSEV, CONSTANTINE PETROVICH (1827–1907), Russian jurist, state official, and writer on philosophical and literary subjects. Born in Moscow in 1827, he studied at the School of Law in St Petersburg, and entered the public service as an official in one of the Moscow departments of the senate. From 1860 to 1865 he was professor of Russian civil law in the Moscow University, and instructed the sons of Alexander II. in the theory of law and administration. In 1868 he became a senator in St Petersburg, in 1872 a member of the council of the empire, and in 1880 chief procurator of the Holy Synod. He always showed himself an uncompromising Conservative, and never shrank from expressing boldly his opinions. Consequently, in the so-called Liberal camp he was always denounced an an “obscurantist” and an enemy of progress. In the early years of the reign of Alexander II. (1855–1881), Pobêdonostsev maintained, though keeping aloof from the Slavophils, that Occidental institutions were radically bad in themselves and totally inapplicable to Russia. Parliamentary methods of administration, modern judicial organization and procedure, trial by jury, freedom of the press, secular education—these were among the principal objects of his aversion. He 