These are principally used for smoking-pipes. Previously to being turned, the meerschaum is soaked in water, it is then worked with ordinary tools, and is described "to cut like a turnip;" after having been dried in a warm room, it is polished with a few of its own shavings, and rubbed with white wax, which penetrates its surface. Sometimes the pipes are dipped into a vessel containing melted wax. *
Amber is principally found on the shores of the Baltic, also at Cromer in Norfolk, etc.: the most esteemed is the opaque kind, resembling the colour of a lemon, and sometimes called fat amber: the transparent pieces are very brittle and vitreous. The German pipe-makers by whom it is principally used, employ thin scraping tools, and they burn a small lamp, or a little pan of charcoal beneath the amber, to warm it slightly whilst
* The meerschaum pipes are made of a kind of fuller's earth, called Keff-kil,
(literally foam-earth,) formerly dug in pita in the Crimea, but now in Anatolia.
The Keff-kill is pressed into moulds upon the spot, dried in the sun, and baked in an oven; the pipes are then boiled in milk, and polished with a soft leather, after which they are carried to Constantinople. They are then bought up by German merchants, who transport them to Pest in Hungary, where, as yet largo and rude, they are soaked in water for twenty-four hours, and then turned in a lathe: the sound ones are for the most part sent to Vienna, where they are finished and often expensively mounted in silver.
They afterwards find their way to all the German fairs, and obtain various prices, from two to forty pounds sterling, those being the most esteemed which, from having been long smoked, become stained of a deep yellow, or tortoiseshellcolour, from the oil of the tobacco. The Keff-kill is used in the public baths at it runs in the lathe, and prevent it from chipping out; they also succeed in bending it, by means of heat. Amber is made into necklaces and ornaments, worn principally in Turkey and India.
Constantinople for cleansing the hair of the woman. See Dr. Clarke's Travels in
Russia,artary, and Turkey, Ac, vol ii. 4th ed. p. 282.
JET, CANNEL COAL, ETC. (2 - 2 1/2).
Jet is found at Whitby, Scarborough, and Yarmouth, and is also imported from Turkey, but it is not generally met in large pieces. It may be turned with most of the tools for the soft and hard woods, and worked with saws and files, all used in the ordinary way. Jet, until polished, appears of a brown colour, and is manufactured by the lapidary into a variety of ornaments, such as necklaces, earrings and crosses.
Cannel coal is principally obtained in England from Yorkshire, Shropshire, Derbyshire, and Cumberland; it is also found in parts of Scotland and North Wales. It occurs in seams, generally about three inches but occasionally one foot thick, amongst ordinary coal; sometimes, as at the Angel Bank Colliery, near Ludlow, it constitutes the entire bed. Compared with jet it is much more brittle, also heavier, and harder; it is less brown when worked, less brilliant, but more durable when polished; neither of them are at all influenced by acids or moisture, although they temporarily expand by heat.
Cannel coal may be thought to be a dirty and brittle material, but this is only partially true; it is far better suited to the lathe than might be expected, although a peculiar treatment is called for in the entire management, which commences with the selection of pieces free from flaws, of a compact grain, and of a clean conchoidal rather than of a flaky structure.
As regards the artificer, cannel coal may be considered to be made up of horizontal layers, and to have a grain something like that of wood. The horizontal surface may be readily distinguished from the vertical, either by its splitting off in flakes, of by its appearing as if varnished at those parts contiguous to the ordinary coal, and which are chipped away as useless; sometimes hard fragments or crystals, apparently of iron ores, interrupt its uniformity of surface, and flaws which show when broken the varnished appearance, occasionally diminish its strength.
The material is cut out with a saw; that for ivory, fig. 49, p. 117, is most proper, but the hand-saw will answer; the pieces are then roughed to the shape with a chopper, or a parallel blade of steel, about eight inches long, one and a half wide, and one quarter thick, sharpened very keenly with two bevils at the one end, and used with the hand alone. For making a snuff-box, whether plain, screwed, or eccentric turned, the plankway, or the surface parallel with the seam, is most suitable; it is also proper for vases, the caps and bases of columns, etc. Cylindrical pieces, as for the shafts of columns, should be cut from either edge of the slab, as the laminae then run lengthways, and the objects are much stronger;* these latter pieces when prepared should be driven into conical chucks with a mallet, as the blow of a hammer near the edge would shiver off a flake lengthways. Cylindrical pieces cut the plankway should be chucked with a hummer, that the blow may be exactly central, otherwise the cylindrical piece would perhaps be broken in two transversely. Cement is also very much used for chucking the work.
All the tools for cannel coal are ground with two bevils exactly like the chisel for soft wood turning, but they are held horizontally; a small gouge, from one quarter to three-eighths of an inch wide, also slightly bevilled off from within, is used for roughing out, or rather bringing the work as near as possible to the shape, to save the finishing tools: these should be ground with thin and very sharp edges, otherwise they burnish instead of scrape the work. The ordinary tools for ivory and hardwood, if employed, must be held downwards at an angle of about twenty degrees; these tools are sometimes used with a wire edge turned up in the manner of a joiner's scraper.
The plankway surfaces turn the most freely, and with shavings much like those of wood, the edges yield small chips, and at last a tine dust, but which does not stick to the hands in the manner of common coal. Flat objects, such as inkstands, are worked with the joiners' ordinary tools and planes; but with these likewise, it is also better the edge should be slightly bevilled on the flat side of the iron. The edges of cannel coal arc harder, and polish better than the flat surfaces.
* Cylindrical pieces thus prepared, say three inches long, and three-eighths of an inch diameter, are so strong they cannot be broken between the fingers; similar pieces have been long since need for the construction of flutes; end in the British Museum may be seen a snuff-box of cannel coal, said to have been turned in the reign of Charles I., end also two busts of Henry VIII., end his daughter Lady Mary, carved in the same material