The form being worked off, it is the pressman’s duty to wash it clean
from every particle of ink, not only for the cleanly working and well
standing of the letter in the subsequent composing, but to save his own
time in making ready when the same letter gets to press again. Many an
hour is lost from not bestowing a minute or two in thoroughly cleansing
and rinsing the form.
For this purpose, printing-offices are provided with a ley-trough,
suspended on a cross-frame, and swinging by iron ears fixed somewhat out
of the precise centre, so that the gravity of the trough will cause it to
fall in a slanting position forward. This trough is lined with lead, the
top front edge being guarded from the pitching of the forms by a plate
of iron. The form having been placed in the trough, on its side, the
pressman takes hold of the rim of the chase by the hook, or instrument
for that purpose, and, laying it gently down, pours the ley upon it, and
sluices it by swinging the trough on its pivots two or three times to and
fro; then, taking the ley-brush, he applies it to the whole form, type,
furniture, and chase; the ley is then let out into a receptacle, and the
form well rinsed with clean water, by swinging the trough as before; the
form is then lifted out, and consigned to the care of the compositor.
The ley is made of pot or pearl ash, or, what is better, of concentrated
ley. A large earthen jar is usually chosen for the purpose; a sufficient
quantity of ash or concentrated ley is added to the water to make it bite
the tongue sharply in tasting.
The ley-brush is made large, the hairs close, fine, and long, in order
not to injure the type, while sufficient force is applied to search every
interstice in the letter where the ink can have insinuated itself.