192 



PIPECLAY 



PIPES 



imperial gallons ; of sherry, 130 imperial gallons ; 

 that <>t Madeira, 110 imperial gallon-: while the 

 common English pi{>e contains 126 wine gallons, or 

 nearly 103 ini]>erial gallons. 



Pipeclay, a line whit plastic clay, very like 

 kaolin, but containing a larger |x*rcentage of silica. 

 For the manufacture nf tobacco-pipes the most 

 desirable clay contains only small traces of limonite 

 iiml alkaline earths. Clays of t hi- nature are met 

 with in Cornwall, Devon, ami Dorset, but the 

 purer varieties of clay u.-ed for pottery-making are 

 also employed in the manufacture. Such clays, 

 Imwever, have siliceous materials added to them 

 artificially, ttjieclay is used by soldiers for 

 whitening lielts, \-c. 



Pipe-fish, a family of remarkable fishes in the 

 same ( Lopiiobranch ) order as the Sea-horses. The 

 Ixxly is elongated like a thin pipe ; the jaws are 

 prolonged in a tubular toothless snout ; the mus- 

 cular development is slight ; the skin is covered 

 with an armature of hart! plates ; the gills are in 

 tin- form of tufts, and the branchial a[>erture is very 

 small. The eggs are carried about and hatched by 

 tin- male, usually within a capacious pouch formed 

 from two folds 'of skin on tne ventral surface of 

 the tail-region. One of the commonest British 

 species is the Great Pipe-fish (Syngiiatlms acns), 

 which is sometimes found in deep water, and some- 

 times at low tide among the seaweed in rock-pools. 

 The specimens commonly seen are from 1 foot to 

 18 inches in length. It may be seen slowly moving 

 about, with curious contortions, poking ite long 

 Knout into every crevice in search of food, and 

 sometimes assuming a vertical position with the 

 head downwards, boring into or stirring the sand. 



Pipe-tigh (Syuyitathtu m 



One of the commonest American pipe-fish is 

 Xi/>honostoma peclrii, which lives among the eel- 

 grasR of the coast 



The name l'i|>e-fish is sometimes given also to 

 the fishes forming the family Fistuhiridie, or Flute 

 mouths, of which one of the most remarkable is 

 the Tobacco .pipe .fish ( t'ixlnlnriii lubaecaria). Hut 

 these are large marine sticklebacks, and have only 

 a superficial resemblance to the true ]>i|' -lish. 



l*i|MTa<*r:r. a natural order of exogenous 

 plants, natives almost exclusively of the hottest 

 part-* of the globe, particularly of Asia and America. 

 A Unit HI s|M-cies ;ire known, to most of which the 

 name Pepper (i|.v.) is sometimes given, although 

 some are also known by other names, particularly 

 those of which the fruit is not used as a spii-'\ 

 but of which Home part is employed for some other 

 purpose, as Betel, Cul>ebs, Matico, and Ava> 



Pi|MTln', an Alkaloid (q.v.) found in ]>epper. 



Pipe-rolls. See KKIORDS. 



Pipe* are made of various materials and for 

 various purposes. Thus, we have ilraining-jiipes 

 for agricultural and sanitary pur|>oHeH, made of 

 earthen wart*, wood, and metal (see DRAINAGE, 

 HKWAOK). pipes of various kinds of metals for a 

 great variety of pur|Mw, and Toliocco-pipes (q.v.) 



of various materials. Earthenware pipes are now 

 made of almost every size, from an inch or two in 

 diameter up to the enormous size of 54 inel.es. 

 They are usually made of fireclay, and are glazed 

 like common Pottery (q.v.). Caoutchouc vulcanised 

 and gutta-percha are also extensively used for 

 making pipes. Leathern pipes are used chiefly for 

 tin- conveyance of water temporarily, as in the case 

 of tire-engines (see FlRE). Metal pipes are made 

 of iron, lead, tin, or an alloy of tin and lead, copper, 

 brass, &c. Iron pipes, as for water and gas, are 

 usually cast, and the manufacture is one of enn 

 mini- extent. See WATER-suri'i.v. 



Pipes of ductile metal, such as brass, copper, and 

 tin, are made by first casting an ingot into the 

 shape shown in fig. 1, with a hole through its 

 length of the same diameter as the bore of the pipe i- 

 intended to have. Into this is placet! an iron toil, 

 called the mandrel (a, fig. 2), which exactly fits, 

 and which projects slightly at the tanered end ( ti, 

 fig. 2). It is then brought to the drawing- table, 

 and here the small end with its projecting mandrel 

 is put into a funnel-shaped hole, drilled through a 

 steel post (a, fig. 3), so as to allow the point to be 



gripped on the other side by a pair of pincers, at the 

 end of a strong chain ; the machine pou cr is then 

 applied to the other end of the chain, antl the soft 

 metal and ite mandrel are drawn through, the 

 former being extended equally over the surface of 

 the latter, which is then removed, and the length 

 of pipe is complete. Some metals require repeated 

 drawing through holes, getting gradually smaller, 

 and have to be softened or unnealed at intervals, 

 as the metal harden* under repeated drawing. In 

 this way brass, copjier, tin, ami pewter pipes are 

 made ; and a patent has also Keen taken out for 

 making steel pipes ; but lead pipes are made of 

 great lengths by squeezing the soft metal through 

 a hole in a steel plate in which there is a fixed core 

 or mandrel projecting, which forms and regulates 

 the size of the bore of the pipe. I'ipc- are also 

 made from copper, brass, anil malleable iron by 



rolling out narrow strips of metal, and then passing 

 them successively through rollers, which are deeply 

 grooved, antl which turn up the edges (fij{. 4). A 

 mandrel is then laid in it, as in fig. 5, ami it is next 

 posed through double-grooved rollers, which turn 

 the edges in, and thus form a complete tul>e round 

 the mandrel. The edges, however, require hard 

 soldering i.e. soldering with a fusible brass alloy, 

 or welding, if of iron. All boiler-tubes used to 

 be made in this way ; but the met hod of draw ing 

 has lately been so much improved Unit copper and 

 brass pi|>es, or tul>es, as thev are frequently called, 

 are now drawn of considerable thickness and 

 diameter. 



