PRE 



PRI 



brings the screw and the swinging bed of 

 the press down upon the bag, and com- 

 presses it into a very small space. A small 

 cord is now passed through the spaces be- 

 tween the pieces of wood, forming the 

 lower side of the swinging bed, and the 

 upper side of the fixed bed, and reefed 

 twice round the bag, and tied fast : the 

 man at the handles now turns it back, and 

 draws up the swinging bed to relieve the 

 bag, the cord retaining it in its compress- 

 ed state. 



In 1798, the Society for the Encourage- 

 ment of Arts, Manufactures, and Com- 

 merce, rewarded Mr. John Peak, of the 

 New Road, near the Adam and Eve, Lon- 

 don, with thirty guineas, for an improved 

 packing press, shown in fig. 3, Plate 

 Press, which is a front elevation of the 

 machine, A A, the frame of the press ; B 

 B, the large screws, which, in this press, 

 contrary to those in common use, are fix- 

 ed and immoveable ; C, a circular iron bar, 

 extending beyond the sides of the press, 

 and having thereon two worms or endless 

 screws, E, E, which work in two toothed 

 wheels, fixed to the nuts ; by turning the 

 winch, D, the nuts and bed are driven up 

 and down the screws, as may be found 

 necessary. F, a stage suspended from 

 the bed, and on which the men stand 

 who work the press ; such a stage may, if 

 found necessary, be fixed at the other end 

 of the bar, another winch being put upon 

 the square shoulder, G. The bed of this 

 press must be formed of two pieces of 

 strong wood, which are held together by 

 screws and nuts passed through them, as 

 shown zthhhh. 



One very considerable advantage of 

 this press is, that much time is saved by 

 its being a double press ; for it will very 

 readily be perceived, that when the low- 

 er package has been sufficiently pressed, 

 as the bed or presser is raised, (another 

 package being thereon) the upper pack- 

 age begins to be pressed, as that one un- 

 derneath is relieved, and so alternately, 

 during the whole operation. 



PRESSING, in the manufactures, is 

 the violently squeezing a cloth, stuff', &c. 

 to -render it smooth and glossy. There 

 are two methods of pressing, viz. cold or 

 hot. As to the former, or cold pressing, 

 after the stuff has been scoured, fulled, 

 and shorn, it is folded square in equal 

 plaits, and a skin of vellum, or pasteboard, 

 put between each plait. Over the whole 

 is laid a square wooden plank, and so put 

 into the press; which is screwed down 

 tight by means of a lever. After it has 

 Iain a sufficient time in the press, they 



take it out, removing the pasteboards, 

 and lay it up to keep. Some only lay the 

 stuff on a firm table, after plaiting and 

 pasteboarding, cover the whole with a 

 wooden plank, and load it with a proper 

 weight. The method of pressing hot is 

 this : when the stuff has received the 

 above preparations, it is sprinkled a little 

 with water, sometimes gum water, then 

 plaited equally, and between each two 

 plaits are put leaves of pasteboard; and 

 between every sixth or seventh plait, as 

 well as over the whole, an iron or brass 

 plate well heated in a kind of furnace. 

 This done, it is laid upon the press, and 

 forcibly screwed down. Under this press 

 are laid five, six, &c. pieces at the same 

 time, all furnished with their pasteboards 

 and iron plates. When the plates are 

 well cold, the stuffs are taken out and 

 stitched a little together to keep them in 

 the plaits. This manner of pressing was 

 only invented to cover the defects of the - 

 stuffs ; and, accordingly, it has been fre- 

 quently prohibited. 



PRIMJE vi<z t among physicians, denote 

 the whole alimentary duct; including the 

 oesophagus, stomach, and intestines, with 

 their appendages. 



PRIMATES, in natural history, the 

 first order of Mammalia in the Linnaean 

 system. The animals in this order are 

 furnished with fore-teeth, or cutting- 

 teeth : the four above are parallel : two 

 breasts on the chests. There are four 



genera, viz. 

 Homo 

 Lemur 



Simia 

 Vespertilio. 



PRIME, an appellation given to what 

 ever is first in order, degree, or dignity, 

 among several things of the same or like 

 kind. Thus, we say, the prime minister, 

 prime cost, &c. Prime is sometimes 

 used to denote the same with decimal, or 

 the tenth part of an unit. In weights it 

 stands for the twenty-fourth part of a 

 grain. 



P RIME fgure, in geometry, one which 

 cannot be divided into any other figures 

 more simple than itself, as a triangle 

 among planes, and the pyramid among 

 solids. 



PRIME numbers, in arithmetic, are those 

 which can be only measured by unity, or 

 exactly divided without a remainder, 1 

 being the only aliquot part, as 3, 5, 7, 11, 

 13, &c : they are sometimes called sim- 

 ple, or incomposite numbers. No even 

 number is prime, because all even num- 

 bers are divisible by 2. Numbers end- 

 in and 5, are not prime, because they 



