gether in the bottom of a little vessel: they furnish an
abundance of smoke, and can be extinguished by covering up the vessel.
The smoke of a wax taper is the best; it is excellent for small plates.

The needle-holder holds short points of various thicknesses, down to the
fineness of sewing-needles.

To sharpen an etching-needle, pass it over the oil-stone, holding it
down flat, and turning it continually. When it has attained a high
degree of sharpness, describe a large circle with it on a piece of
card-board, holding it fixed between the fingers this time, and go on
describing circles of a continually decreasing size. The nearer you
approach to the centre, the more vertical must be the position of the
needle. The fineness or the coarseness of the point is regulated by
keeping the needle away from, or bringing it nearer to, the central
point.

The dry point must be ground with flat faces rather than round, so as to
cut the copper, and penetrate it with ease.

If the burnisher is not sufficiently polished, it scratches the copper,
and produces black spots in the proofs. To keep it in good condition,
cut two grooves, the size of the burnisher, in a piece of pine board.
Rub it up and down the first of these grooves, containing emery powder;
and then, to give it its final lustre, repeat the same process, with
tripoli and oil, in the second groove.

The stones which are too hard for razors are excellent for the scrapers.
Having sharpened the scraper with a little oil, during which operation
you must hold it down flat on the stone, pass it over your finger-nail.
If the touch discloses the presence of the least bit of tooth, and if
the tool does not glide along with the greatest ease, the grinding must
be continued, as otherwise the scraper will scratch the copper.

You are at liberty to use two troughs,--one for the acid bath; the
other, filled with water, for washing the plate.

A glass funnel, and a bottle with a ground-glass stopper, will be
necessary for filling in and keeping the etching liquid.

Various substances are used for finishing off the copper plates; the
most natural is the paste obtained by rubbing charcoal on the oil-stone
with oil.

Then comes the fine emery paper Nos. 00 or 000, rotten-stone, tripoli,
English red, and, finally, slate. Powdered slate, produced by simply
scraping with a knife, is excellent, used with oil and a fine rag, the
same as other substances.

The varnish for revarnishing