That which flows from the lower incisions is often collected on tiles or on a concave piece of the prickly pear (Opuntia), but is less crystalline and more glutinous, and is less esteemed.
Between these three or four longitudinal incisions are then made, the utmost care being taken not to injure the inner bark.
In copperplate printing the whole of the plate is first inked, the flat surface is then cleaned, leaving ink in the incisions or trenches cut by the engraver, so that, when dampened paper is laid over the plate and pressure is brought to bear, the paper sinks into the incisions and takes up the ink, which makes an impression in line or lines on the paper.
2, a), great care being taken not to let the incisions penetrate to the interior lest the juice should flow inside and be lost.
2, b) in most districts (although in some the incisions are made horizontally, as in Asia Minor), the " nushtur " or cutting instrument being drawn twice upwards for each incision, and repeated two to six times at intervals of two or three days.