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part at one end, too short to be conveniently used asterthe rest has been worn and cut away, is left unfilled with.the black-lead, that there may be no waste of so valuablea commodity. These pencils are greatly preferable to theothers, though seldom so perfect as could be wished, beingaccompanied with some degree of the fame inconveni-ences, and being very unequal in their quality, on accountof different forts of the mineral being fraudulently joined'together in one pencil, the fore part being commonly prettygood, and the rest of an inferior kind. Some, to avoidthese imperfections, take the finer pieces of black-leaditself, which they saw into Hips, and fix for use in port-crayons : this is doubtless the surest way of obtainingblack-lead crayons, whose goodness can be depended on.

V. Black vegetable ^juices.

The excellent black varnish of China and Japan, whichhas hitherto been but imperfectly imitated in Europe, andwhich was formerly thought to be an artificial compositionof resinous bodies coloured with black pigments, has beendiscovered, by the later travellers in those countries, to bea native juice, exuding from incisions made in the trunksof certain trees. One of these trees, according to the ac-count given of it in Kæmpfer’s Amanitates exotica , is thatwhose fruit is sometimes brought to Europe, as a medicinaldrug, under the name of anacardium.

The anacardium itself, as it comes to us, is remarkablefor a black-colouring juice. It is a kind of nut, with adouble shell, containing, in the space between the outerand the inner shell, a fungous substance filled with a dark-coloured viscous fluid, which is easily forced out, by cut-ing the nut, and squeezing it between the fingers: a littlewarmth, by liquefying the thick matter, makes it comeout more freely; though the quantity obtained, either withor without heat, is not very considerable. This juice, rub-bed