the
margin of the plate, if that be wide enough, or on a separate plate, and
is taken up by the dabber. The plate to be regrounded must of course be
warmed as for laying a ground with the roller, and care must be taken
not to have the dabber overcharged with ground.

[14] (p. 40.) In default of the charcoal-paste, rubbing with the finest
emery-paper will do to remove the polish.

[15] (p. 40.) I cannot direct the reader to a copper-planer, and
therefore it will be best to give some directions for removing faulty
passages. The following paragraphs are copied bodily from Mr.
Hamerton:--

"The most rapid way is to use sandpapers of different degrees of
coarseness, the coarsest first, and then the scraper, and, finally,
willow charcoal with olive oil. The charcoal will leave the surface in a
fit state to etch upon.

"This scraping and rubbing hollows out the surface of the copper, and
if it hollows it too much the printing will not be quite satisfactory in
that part of the plate. In that case you have nothing to do but mark the
spot on the back of the plate with a pair of calipers, then lay the
plate on its face upon a block of polished steel, and give it two or
three blows with a hammer (mind that the hammer is rounded so as not to
indent the copper)."

[16] (p. 48.) The process here alluded to is the one used by Mr. Haden.
The mordant is the so-called Dutch mordant, and the manner of making it
is thus described by Mr. Hamerton:--

"First heat the water by putting the bottle containing it into a pan
also containing water, and keep it on the fire till that in the pan
boils. Now add the chlorate of potash, and see that every crystal of it
is dissolved. Shake the bottle to help the solution. When no more
crystals are to be seen, you may add the hydrochloric acid. Make a good
quantity of this mordant at once, so as always to have a plentiful
supply by you."

For a full account of the Haden process see Mr. Hamerton's "Etcher's
Handbook," or the second edition of his "Etching and Etchers."

This Dutch mordant is preferred to nitric acid by many etchers,--even
when working, not in the bath, but in the ordinary way, as taught by M.
Lalanne,--because it bites down into the copper, and hardly widens the
lines. "From my experience," writes Mr. Jas. D. Smillie, in a letter now
before me, "I unhesitatingly prefer the Dutch mordant for copper; it
bites a very fine black line, it is not so severe a trial to the ground,
and it