learn something by your failures, as
your experience in one case will teach you what to do in others.
Self-acquired experience is of all teachers the best.

72. =Various other Methods of Biting.=--The two preceding methods,
which, in a general way, comprehend the rules of biting, do not exclude
other particular methods of a similar nature. Thus, it may be well
sometimes to etch at first only the simple outline, biting it in more
or less vigorously, according to the nature of the case (see Pl. IV.
Fig. 3); and then, having revarnished and resmoked the plate, to
elaborate the drawing by going over it either in some parts only or
throughout the whole. Rembrandt often pursued this course; and we may
follow the several stages of his work by studying the various states of
his plates. We see that he took great pains to work out some part of his
subject very carefully, without touching the other parts; he then took a
proof, and afterwards went over the same part with finer lines, and
passed on to the other parts, treating them according to the effect
which he desired to reach.

This method is often imitated; it is employed when it is necessary to
lay a shadow over a passage full of detail, as, for instance, in
architectural subjects, in the execution of which it is easier, and
tends to avoid confusion, to fix the lines of the design first, and
then, having laid the ground a second time, to add the shadows. (See Pl.
IV. Fig. 4.)

"Pardon me! But might not this result be obtained by the same biting, if
the lines of the design were drawn with a coarse point, and the shading
were added with a finer one?"

Certainly; and in that case we should have an instance of work executed
with several needles, such as I pointed out to you before.

From the explanations previously given, it will be clear, also, that,
the nature of the subject permitting, it may be advantageous sometimes
to execute a plate by drawing and biting each distance by itself. Thus
you may commence with the foreground, and may bite it in; having had a
proof taken, revarnish your plate, and proceed in the same fashion to
the execution of the other distances, and of the sky, always having a
proof taken after each biting to serve you as a guide.

This mode of operation--essentially that of the engraver--is of special
advantage in putting in a sky or a background behind complicated
foliage. You can draw and bite your sky or your background all by itself
(see Pl. IV.