590 



PLYMOUTH PO. 



intervening town of East Stonehouse. The town hav- 

 ing gradually risen from the condition of a small ilsh- 

 iiiir town to its present size, most of the streets are 

 irregular, and by no means elegant or commodious ; 

 but the new parts of the town are handsome, and 

 are spreading rapidly. The public buildings are, 

 the custom-house, the exchange, the Athenasum, the 

 public library, the theatre, the royal hotel, places of 

 worship, the classical and mathematical school, the 

 mechanics' institute, &c. Plymouth is divided into 

 two parishes. Of the two parish churches, the most 

 ancient is that of St Andrew, built previously to 

 1291, a handsome building of the Gothic order; 

 Charles's church is also a Gothic structure. Among 

 the charitable institutions, which are about thirty, 

 are a work-house, a public dispensary, an eye in- 

 firmary, a lying-in charity, a public subscription 

 school, alms-houses, Bible societies, &c. &c. Gov- 

 ernment has several military and naval establish- 

 ments at this port. Of the fortifications, the most 

 remarkable is the citadel, which was erected in the 

 reign of Charles II. It was placed in a most com- 

 manding situation on the eastern end of the height 

 called the Hoe (which shelters the town from the 

 sea). It is exceedingly well fortified, and is con- 

 stantly garrisoned, It contains the residence of the 

 governor of Plymouth, and barracks for five or six 

 hundred troops. Under the eastern walls of the 

 citadel is the victualling office, an extensive range 

 of buildings, containing the granaries and ovens for 

 supplying the bread, as also the cellars and store- 

 houses for wine, spirits, meat, &c., for the use of the 

 king's vessels in harbour. The port of Plymouth 

 is distinguished for its capacity, and the security 

 which it affords in its several parts, It is capable 

 of containing 2000 sail, and is one of the finest har- 

 bours in the world. It consists of three divisions 

 or harbours, Sutton pool, immediately adjoining 

 the town ; Catwater, an extensive sheet, formed by 

 the estuary of the Plym ; and the harbour or bay of 

 Hamoaze. At the mouth of these harbours the 

 great bay of Plymouth sound forms an excellent road- 

 stead, which is now completely secure by the erec- 

 tion of the breakwater across its entrance. This 

 work is an insulated mole, or vast heap of stones, 

 stretching across the entrance of the sound, so far 

 as to leave a passage for vessels at either end, and 

 opposing a barrier to the heavy swell rolling in from 

 the Atlantic. Its length is 1760 yards, the eastern 

 extremity being about 60 fathoms to the eastward of 

 St Carlos's rocks ; and the western, 300 west of the 

 Shovel rock. The middle part is continued in a 

 straight line 1000 yards, and the two extremities in 

 cline towards the northern side of the straight part 

 in an angle of about 120 degrees. This great work 

 was begun Aug. 12, 1812. During its progress, 

 convincing proofs of its efficacy and utility were af- 

 forded . The expense of erecting the breakwater is 

 estimated at ] , 1 7 1 ,100. The Eddystone light-house 

 is an important appendage to the harbour ; the en- 

 trance of which would, without this beacon, be ex- 

 tremely dangerous. (See Eddystone.) Besides the 

 importation of coals, culm, corn, wine, timber, and 

 articles for home consumption, Plymouth carries on 

 a considerable trade much promoted by the estab- 

 lishment of a chamber of commerce, in the year 

 1813. The garrison at this port is under the com- 

 mand of a military officer styled the governor, who 

 is also generally commander-in-chief of the western 

 district. The naval affairs are under the direction 

 of the port-admiral, whose residence is at Devon- 

 port. In the 18th year of Henry VI., Plymouth was 

 incorporated as a borough. Plymouth is 218 miles 

 from London, and 44 from Exeter ; Ion. 4 T W. ; 

 lat. 50 93' N. Population in 1841, 75,599. 



PLYMOUTH ; a post-town, port of entry, and 

 shire town of Plymouth county, Massachusetts, form- 

 erly the capital of the Plymouth colony, and the 

 oldest town in New England. It was settled by the 

 pilgrims, who arrived in the May Flower, Decem- 

 ber 22, 1620. It stands on a fine harbour of the 

 same name, 36 miles south-east of Boston. The 

 court-house is in lat. 41 57' N. ; Ion. 70 42' 30* 

 W. The township, though often divided, is still sixteen 

 miles long, and five broad. The harbour is spacious, 

 but shallow. The town has considerable commerce, 

 and valuable manufactures of iron. An elegant hall 

 has been erected for the use of the Pilgrim society. 

 Population, in 1820, 4348 ; in 1830, 4751. The 

 Indians called this town Accomack. A part of the 

 rock on which the pilgrims landed has been conveyed 

 to the centre of the town. 



PLYMOUTH, COLONY OF. See Ne England. 



PNEUMATICS (from the Greek vnvpa., air) is 

 that branch of natural philosophy which treats of the 

 mechanical properties of elastic fluids (see Elasti- 

 city'), the inelastic fluids belonging to the province of 

 hydraulics and hydronamics (see the articles'). The 

 elastic fluid with which we are most familiar is at- 

 mospheric air ; and it possesses all the mechanical 

 properties, which it is necessary to notice in any 

 elastic fluid. The laws of pneumatics will be found 

 treated of under the heads of Air, Air-pump, Barom- 

 eter, Pump Acoustics. 



PNEUMONY ; inflammation of the lungs. The 

 species, according to Cullen, are peripneuniony and 

 pleurisy. (See Pleurisy.) The most general cause 

 of this inflammation is the application of cold to the 

 body, which gives a check to the perspiration, and 

 determines a great flow of blood to the lungs. It 

 attacks principally those of a robust constitution and 

 plethoric habit, and occurs most frequently in the 

 winter and spring. Other causes are violent exer- 

 tions in singing, speaking, or playing on wind instru- 

 ments. The true peripneumony comes on with an 

 obtuse pain in the chest or side, great difficulty of 

 breathing (particularly in a recumbent position, or 

 when lying on the side affected), together with a 

 cough, dryness of the skin, heat, anxiety and thirst. 

 If relief is not afforded in time, and the inflammation 

 proceeds with violence, the face will alter to a pur- 

 ple colour ; an effusion of blood will take place into 

 the cellular substance of the lungs, so as to impede 

 the circulation through that organ, and the patient 

 will soon be deprived of life. When it goes off by 

 resolution, some very evident evacuation attends it ; 

 the evacuation which most frequently terminates the 

 complaint, and which does it with the greatest ef- 

 fect, is a free and copious expectoration of thick 

 white or yellow matter, slightly streaked with blood ; 

 and by this the disease is carried off generally in the 

 course of ten or twelve days. 



PO (Padus, Eridanus), the largest river of Italy, 

 rises in mount Viso, in the Cottian Alps, Piedmont, 

 at an elevation of 6000 feet above the sea. It flows 

 from west to east through Piedmont, and from Pavia 

 forms the southern boundary of the Lombardo-Ven 

 etian kingdom, which it separates from the Sardinian 

 territories, from Parma, Modena, and the States of 

 the Church. It receives, during a course of 320 

 miles, the Doria, Sesia, Tessino, Adda, Oglio and 

 Mincio from the left, the Tanaro with theStura,the 

 Scrivia, Trebia, Taro, Lenza, Crostolo, Sechia, Pa- 

 naro and Reno from the right, and empties itself by 

 four mouths into the gulf of Venice. It is the main 

 channel of commercial communication in Upper 

 Italy, but it often does great mischief by its inunda- 

 tions, and it occasionally changes its bed ; the 

 swamps which it leaves are used for the cultivation 

 of rice. In many parts of its course it is confined by 



