PIETISTS 



Pietists. Word used vaguely 

 for mystics of many types often 

 as a term of contempt. It refers 

 strictly to a group of Lutheran re- 

 formers, who arose in Germany 

 about 1670, under the leadership 

 of Philip Jacob Spener (1635- 

 1705). He was a Lutheran pastor 

 at Frankfort who held devotional 

 meetings called collegia pietatis, 

 whence the name, and established 

 a kind of Methodism. He taught 

 no special doctrines, and founded 

 no sect, confining himself to an 

 endeavour to promote spiritual 

 life generally ; but some of his fol- 

 lowers adopted a dress and customs 

 rather like those of the Quakers. 

 Under A. H. Francke (q.v.), Halle 

 became the centre of the move- 

 ment, which had much influence for 

 good, but afterwards degenerated 

 into bigotry and emotionalism. 

 See Mysticism. 



Pietra Dura (Ital., hard stone). 

 Inlaid work consisting of black 

 marble, jasper, agate, or other hard 

 stones inlaid in wood or marble. 

 It is sometimes called Roman 

 Mosaic, but should be distinguished 

 from mosaic proper, which is em- 

 bedded in cement. See Mosaic. 



6 147 



consisted of a thick 

 glass tube closed 

 at each end by a 

 brass cap, one of 

 which was fitted 

 with another tube 

 containing a piston 

 or screw plug, for 

 applying pressure 

 to the liquid in the 

 first tube. This 

 latter tube was fit- 

 ted with a flask, the 

 neck of which was 

 drawn out into a 

 thin tube and. 

 graduated. P r e s- 

 'show- sure on the Bqukl is 

 ing working communicated 

 parts. See text to the liquid in the 

 flask by means of 

 a system of valves, and the amount 

 of compression read off on the 

 graduated tube. In the figure, a is 

 the piezometer body, b, the tube 

 extension containing floating glo- 

 bule c of mercury enabling the 

 compression of the liquid to be 

 read off on the graduated scale d, 

 e is a pressure gauge or mano- 

 meter, the pressure being shown 

 by the height to which the liquid 



Pietermaritzburg, South Africa. Plan of the capital city of the province of Natal 



Pietre Mill. Battle ground in 

 France. Also known as Moulin le 

 Pietre, it was a German strong 

 position adjoining the village of 

 Pietre, slightly N.E. of Neuve 

 Chapelle, on the river des Layes. 

 Both were prominent in the battle 

 of March, 1915, the British 21st 

 brigade being held up by heavy 

 machine-gun fire at the mill on 

 March 10. The village was reached 

 by men of the 7th division two 

 days later. See Neuve Chapelle, 

 Battle of. 



Piezometer (Gr. piezein, to 

 press ; metron, measure). Instru- 

 ment for measuring the compressi- 

 bility of liquids under varying 

 pressure. The first piezometer was 

 invented by Oersted in 1882, and 



rises in the tube. The hand wheel 

 with screw, /, and piston enables 

 pressure to be applied. 



Pig. Name applied to members 

 of the family Suidae, which 

 forms part of the even-toed group 

 of the zoological order Ungulata 

 or hoofed mammals. The tribe 

 includes the true pig, bush pig, 

 wart hog, and babirusa. The 

 typical pigs include over a dozen 

 species, the domesticated pig being 

 merely a modified variety of one or 

 more of the wild forms. 

 1 Pigs are distinguished from the 

 ungulates nearly related to them 

 by the very long head, terminating 

 in a flattened disk-like snout, in 

 which the nostrils are placed. The 

 existence of this snout involves the 



PIG 



presence of an additional bone in 

 the skull for its support. Pigs have 

 conspicuous tusks in both upper 

 and lower jaws, the upper ones 

 being reflected upwards, instead of 

 pointing downwards as in most 

 other animals. Each foot has four 

 toes, of which only the middle two 

 touch the ground when walking. 

 Most of them have large and often 

 pendent ears ; their hair consists of 

 bristles set comparatively far 

 apart ; and the tail is more or 

 less bare, with a tuft at the tip. 

 Pigs are not ruminative animals, 

 having a simple and undivided 

 stomach. 



Of the various wild species, the 

 European wild boar is the best 

 known. All wild pigs frequent 

 marshes and damp places, and this 

 trait is seen in the love of the tame 

 pig for wallowing in any mud it 

 can find ; while the habit of turn- 

 ing up the ground with its snout 

 is a survival of the root-hunting 

 methods of its wild ancestors. The 

 Chinese appear to have been the 

 first race to pay attention to the 

 domestication of the pig, though 

 its remains are found in Swiss 

 lake dwellings. The date of its 

 domestication in Great Britain 

 is unknown. 



There is little doubt that the 

 domesticated breeds are the de- 

 scendants of the wild swine of the 

 various countries, the British breeds 

 being derived from the European 

 wild boar, but they have been 

 greatly modified by crossing with 

 Chinese and other Asiatic breeds. 

 Probably as a result of these 

 crosses, domesticated swine have 

 undergone many modifications, 

 even the number of teeth and the 

 vertebrae having changed. The 

 skull has become altered in shape, 

 for example, so that the straight 

 face of the wild swine has given way 

 to the concave one of most of the 

 modern breeds. 



Of the white breeds, the large, 

 middle, and small Yorkshire, and 

 the curly coated pig of Lincolnshire 

 are the most important. The 

 large white sometimes reaches 

 a live weight of ten hundred- 

 weight, yields a better propor- 

 tion of lean to fat than most 

 other breeds, matures early, and 

 turns out equally well for small 

 pork or for heavy bacon flitches. 

 It is a hardy breed, and of quiet 

 and restful disposition an im- 

 important point with the fattener. 

 The sow is very prolific, and makes 

 an excellent mother. 



The middle white is the result of 

 a cross between the large and small 

 breeds, and combines the good 

 pomts of both. It has a short 

 head, turned-up snout, and a 

 general air of compactness. It is 



