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PLOT'TING. The art of laying down o 

 paper the angles and lines of a survey, by 

 admeasurement from the field book. 



PLOT'TING TABLE. An improved de 

 soription of plane table. 



PLOT'US. A genus of birds ; the Darte rs. 

 Order Palmipedes: family Totijxilmatce, 

 The habits are similar to those of the 

 pelicans ; the body is about the size of a 

 duck, but the neck is long. Name plotus, 

 or plautus, flat-foot. 



PLOUGH. 1. An agricultural machine for 

 turning up the soil, preparatory to re 

 ceiving the seed; and of which there are 



numerous forms. 2. A bookbinder's 



machine, for cutting the edges of books. 



3. A description of plane used by 



Joiners. See PLANE. 



PLOUGH'SHARE. The part of a plough 

 which cuts the ground at the bottom of 

 the furrow, aiid raises the slice to the 

 mould-board, which turns it over. 



PLUG. In architecture, a piece of wood 

 driven into a wall, to afford holding-sur- 

 face for fixtures. 



PLUG AND FEATHER. Key and Feather. 

 A mode of dividing hard stones, by means 

 of along wedge called the key, and wedge- 

 shaped pieces of iron called feathers. 



PLUM. A fruit of several species, 

 especially that of the Prunus domestica, 

 said to have been introduced into Eng- 

 land in the 15th century, and now culti- 

 vtod over all parts of the country. There 

 are, it is said, about 300 varieties of this 

 tree. There io also the Bullace Plum of 

 Britain, the Myrobalan Plum of the 

 United States of America, and the Black 

 Plum of Canada. 



PLUM'B, } A. weight of lead, hung to 



PLUM'MET. ) a string, to sound depths; 

 or on a level, to mark the perpendicular. 

 See PLUMB-LINE. 



PLCMBA'OO. 1. Graphite or black lead : 



from plumbum, lead. See BLACK-LEAD. 



2. Lead-wort. A genus of plants, mostly 

 shrubs. Pentandria Xonogynia. Warm 

 climate*. 



PLUMB'BR BLOCK. In mechanics, a 

 carriage fastened on to any contrivance, 

 and adapted to support a shaft or axle. 



PLUMB-LIUB. An instrument chiefly 

 used by builders, consisting of a leaden 

 bob, suspended to the end of a line, used 

 to determine the perpendicularity of 

 their structures to the horizon. The 

 Plumb-rule is used for the same purpose ; 

 but in this the bob is suspended to the 

 end of a straight board, with a line 

 marked down the middle, so that when 

 the edge of the board is placed against 

 the wall, or other object, the plumb-line 

 shall exactly coincide with the line 

 marked upon the board. 



PLUMB'ERT. 1. The art of casting and 

 working lead. Such tradesmen are called 

 plumbers. 2. Works in lead. 



PLUME, 1 Lat. plumula. dim. of plu- 



PI.U'MULB. ] ma, a feather. A littl'- 

 feather. The expanding embryo or germ 

 of a plant, within the seed, resembling % 

 little feather, and which speedily becomes 

 a tuft of young leaves, with which the 

 young stem, if there be any, ascends. 



PLUME'-ALUM. A variety of asbestos. 



PLUMO'SE, Lat. plwnosus. Feathery, 

 downy. 



PLUM'MET. See PLUMB and PLUMB-LINE. 



PLUNG'ER. A long solid cylinder, some- 

 times used in force-pumps, instead of the 

 ordinary pistons or buckets. 



PLURALITY. In ecclesiastical late, the 

 holding of more than one benefice. 



PLUS. A Latin word signifying more. 

 Used in algeli-a as the name of the cha- 

 racter + , which denotes that the quantity 

 before which it is written is additive. 



PLUSH, Germ, pltuch, shag. A sort of 

 shaggy cloth or stuff, with a velvet nap 

 on one side, composed regularly of a woof 

 of a single thread and a double warp : the 

 one, wool of two threads twisted : the 

 other, of goat's or camel's hair. Some 

 plushes are, however, made wholly of 

 worsted, others wholly of hair. 



PLUTON'IC. Relating to Pluto, the my- 

 thological king of the infernal regions. 

 The epithet is applied, by geologists, to 

 certain rocks elaborated in the deep re- 

 cesses of the earth. The plutonic rocks 

 are those unstratified crystalline forma- 

 tions, such as granites, greenstones, and 

 others of igneous origin, formed at great 

 depths, whereas the volcanic rocks are 

 solidified at or near the surface. 



PLUVIAM'ETER, from pluvia, rain, and 

 /MTfor, measure. A rain-gauge ; an ap- 

 paratus for ascertaining the quantity of 

 rain which falls at the place where the 

 observations are made. 



PLY'ERS. In fortification, a kind of ba- 

 lance or timber levers, for raising or 

 letting down a drawbridge. 



PLTM'OUTH MARBLE. Averyfine variety 

 of marble, found in various parts of De- 

 vonshire, especially near Plymouth. The 

 ground is bluish- white, varied with veins 

 of pale red, with some of brown and yel- 

 low. It takes a fine polish. 



PNEUMAT'IC. Appertaining to air 

 or gas. UttufAoc,, wind. The chemist re- 

 quires a large quantity of pneumatic appa- 

 ratus in experimenting on gases. 

 PNEUMAT'ICS, from xvii>/jta,Ti}cr l , from 

 livutM, wind. The branch of science 

 which relates to the equilibrium and mo- 

 ions, and other mechanical conditions 

 ind properties, of aeriform fluids, as their 

 weight, density, compressibility, and elas- 

 ticity. 

 PNEUMATOL'OOT, from vtiiu t wt, air, and 



iy;. discourse. 1. Pneumatics. 'i. 



The doctrine of spiritual existences. 





