Hero's Belopoeica (Treatise on Artillery Construction)

the claw hand or finger original Greek: χεὶρ ἤτοι δάκτυλος (cheir ētoi daktylos) marked with the letters ΝΞΟ; the two uprights holder original Greek: κατοχεύς (katocheus) and little post original Greek: στημάτιον (stēmation).

The entire weapon is composed of the following parts:
the bow elbow original Greek: ἀγκών (ankōn); referring here to the bow arm with the bowstring;
the pipe with the label SYRINX original Greek: CYPIΞ; the grooved wooden stock of the engine, the left side ΕΖ is fully drawn, the right side is interrupted, and the lower end with the letter Θ is drawn too far to the left;
the slider, inserted at the bottom in a dovetail shape, with the arrow-groove bow-rest original Greek: ἐπιτοξῖτις (epitoxitis) and the hump, consisting of the 2 uprights, the bolt, and the claw that rotates around it;
the cocking wood German: Spannholz, located at the rear of the pipe with the concave notch for the belly and the two hand-grips;
the pawl ΓΔ runs—specifically one on each side—over the teeth of the ratchet German: Zahnstange during the cocking process and holds the tension fast. ΑΒ indicates the position of the pawl on the slider.

The accompanying scale drawings (Figure 4, page 10) with the labels from both diagrams in manuscripts M and P are likely understandable even without a description.

According to the description, the slider should be just as wide as the pipe; in practice, this is completely impossible. In any case, only the rear part is meant, because there must also be room for the ratchets on both sides of the slider. In the illustrations, the slider is significantly narrower than the pipe.