MANUFACTURES.
SIS
Manufac- the glass are only seen indistinctly through it, a greattures. degree of blackness may be given to them by dustingthe surface of the glass over with dry lamp-black, andthen rubbing it off with a soft camel-hair brush verylightly applied: the traces made by the crayon being3omewhat adhesive, the lamp-black will be fixed on themby the action of the brush, while it is swept off from therest of the surface. The crayons are made of threedegrees of hardness to suit any climate, and are notacted on by water, either fresh or salt. Asphaltum andyellow bee’s-wax, in equal proportions, are melted toge-ther, and then lamp-black, just sufficient to give it acolour, is stirred in. The mixture is then cast intosticks, and forms a crayon suitable for a temperatedegree of heat ; but for very hot weather, the hardestkind of heel-ball, lowered with a little tallow, answersadmirably. The glass plate, previous to drawing on it,should be rubbed well with a leather, in order to forcefrom it any moisture or dirt, and the artist, while makingthe drawing, should wear a finger-stall. It is sometimesdifficult to bring the crayon to a fine point with a com-mon penknife, for if the edge of this latter is set to theshape of a very fine wedge it will slip through thecrayon, and, on the other hand, a blunt edge will breakoff the point before it has been cut sufficiently fine ; butif the knife is set chisel-shaped, the oblique surface beingapplied next to the crayon, shavings of extreme tenuitymay be taken off and a very fine point will be theresult.
Manufacture of Steel Pens.
Steel pens. (1137.) The extraordinary extent of this manufacturerenders it necessary that we should say a few words onthe subject, although there is nothing very remarkableto describe. The steel is rolled into very thin platesthe usual thickness of these pens, in pieces about 4 inchesbroad and 3 feet long. These are then placed succes-sively under a stamping press, such as we have describedunder button-making, and pieces of the proper form forthe pens are cut out with great rapidity. The nib isthen introduced into a gauged hole of the proper formto receive it; it is then pressed into the cylindricalform, and the slit and other openings in the pen formedin like manner: they are then cleaned, and ultimatelytempered. The cleaning is performed in a very curiousmachine. This consists of a tin cylinder about 8 or 9inches in diameter and 3 feet long, with a hole in themiddle of its length for putting in and taking out thepens, which hole is covered by a lid. The cylinder ishung on joints at each end to cranks formed one on eachof two axles. These are furnished with a fly-wheel,and one of them with a handle. As this latter is turned,therefore, the cylinder is thrown up and down, andbackwards and forwards, each end and every part ofcourse describing a circle, whereby the pens are rubbedone against another, and ultimately come out beautifullybright and clean. This operation is carried on for threeor four hours; but many thousand pens are operatedupon at the same time.
Quill pens (1138.) Making quill pens by machinery .—Short
made by quill pens are sold properly formed for writing, which are
,rac inery. cut y,y machinery as follows. The top and bottom of thequill being cutoff, the open piece is run upon a cylinder,on to which it slips easily, and, being placed in amachine, two cutting edges are run along it, one oneach side, forming the quill into two semicylindrical
pieces. These are laid in grooves with the round part Mechanicsdownwards, and a plane run over the upper side or Processesedges to make them smooth. They are then cut infrproper lengths, two or three being formed out of eachlength, that is, four or six out of each quill. Eachpiece is now brought to the nibbing machine, which isa kind of cutting press, and each is lastly finished offwith a few touches by hand from a sharp penknife.
(1139.) The best pencils of this kind are made from Blacka natural ore of plumbago obtained from Borrowdale, in 1"®“ 6Cumberland; but the more common sort from an arti-ficial compound of plumbago dust and antimony. Thelumps of pure plumbago, when scraped and freed fromdirt, are of irregular form, varying generally in sizebetween that of a walnut and an egg. These lumpsare cut into slices of about the thickness of a shilling bya small circular saw, which is put in motion by theworkman turning a winch and fly-wheel with one hand,while he applies the lump of ore with the other againsta metal face set at a proper distance from the disc otthe saw, so as to act as a gauge or stop for producingthe proper thickness in the slice. The saw runs ver-tically, and the ore is applied below it, the workmangradually raising it against the saw till tnj piece is cutoff, when it falls down slice upon slice on a table below,these being of different sizes, from one to two inches mlength, and of variable breadths. One edge is now madequite straight, and the insertion of the lead into thepencil commences. First, however, it should be ob-served that pieces of cedar are cut by a fine circularsaw into square prisms of the intended length of thepencil, or rather into such thickness that two of themtogether form a square, one of them thicker than theother, so as to admit the groove cut to receive the leadto be in one piece only, this groove being ploughed outby a proper gauge plane. The workman takes nowone of the slices of plumbago brought to a straighedge, and dips this straight edge into glue, he theninserts it in the groove, and with a sharp instrumen
makes a cut on each side along the edge of the woo ,
when by a slight force it breaks off, leaving again astraight edge. This is now dipped again in glue, aninserted at the end of the last piece, and again cu *Ji ’till the length of the groove is filled with the lead,whole upper surface is then smoothed, and the o ^piece of wood glued on; the pencil is then squarerather rough. t0
It is now taken to be made round, preparatory^which it is passed along a circular saw set to an e ^ ^gauge, and cut also to a certain length. In or e ggive it its cylindrical figure it is passed through asq ^hole in an iron or steel puppet of the exact S]Z ® °pencil, and forced along by the workman. tus
other side of this puppet is the revolving a PPf u _ eSjwhich cuts the pencil round; it consists of two ^and a small plane iron revolving round an °P en , . aSBeyond this is a cylindrical hole in a stee p . ’ u{soon, therefore, as the first end of the P en '~* rg t j,eround it is forced into this circular hole, and, rc j a tworkman has lost the means of pushing i ° . e d
the end that is square, the cylindrical en ge j ze
through the circular hole, so as to enable i j, e( l
it with a pair of wooden nippers; and it is at jf u Ilyand drawn quite through, and comes ou
dead
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