HERON’S ARTILLERY CONSTRUCTION CHAPTERS 9 AND 10

| English Translation (from Greek) |

| English Translation (from German) |
| :--- | :---: | :--- |
| ...to pull back the arms. Therefore, instead of the so-called pull-back lever original: "katagōgis" described in the previous theorem, they added an axle original: "axōn" to the pipe original: "syrinx" at its rear 5 end, turning easily in a transverse position. At its ends they made square hand-spikes original: "skytalas" and used them to turn it. By this rotation, it happened that the 10 slider original: "diōstra" was pulled back, carrying the bowstring in the following way: for from the ends of the slider near the small claw-mechanism original: "chelōnarion" they attached ropes and connected them to the mentioned 15 axle; when these were wound up, the pulling back occurred. In the case of larger engines, it happened that even so the arms could only be pulled back with 20 great force; hence they pulled them back with a pulley system original: "polyspaston". They attached one block original: "manganon" of the pulley system to the claw-mechanism, and the other to the end of the pipe at the axle or capstan original: "oniskos", literally "little ass", and the... | | ...a correspondingly large force is necessary. Instead of the tensioning lever just mentioned, a horizontal shaft original: "Welle" was attached to the rear end of the pipe, which could be turned easily; at its ends, four-sided hand-spikes original: "Handspeichen" were inserted, with which it was turned. Through this rotation, the slider original: "Schieber" along with the bowstring is pulled back in the following manner. At the end of the slider where the trigger mechanism original: "Abzugsvorrichtung" is located, ropes were attached and connected to the mentioned shaft; by the winding up of the ropes, the tensioning was achieved. With larger artillery pieces, however, the arms could only be pulled back with difficulty even in this way; therefore, the pulley system original: "Flaschenzug" was used here for tensioning. One block original: "Kloben"¹ of the pulley system was placed next to the trigger, the other next to the shaft or the... |

1 pulled back original: "katagesthesai" in manuscripts P and V: to occur original: "katagenesthesai" in manuscript M       3 added in M: placed upon in P and V       7 of a square hand-spike in M     making in M, P, and V: inserting suggested by R. Schöne       10 carrying — pulled back (line 18) is missing in M       12 of the suggested by Köchly: the in M, P, and V       16 engines suggested by R. Schöne       17 even so suggested by Thévenot: really in P and V       force in P and V       23 at the in M: towards the in P and V       capstan in M: the capstan in P and V

¹ Instead of "pulley block," it should probably be "end of the rope" here. In that case, three stages of force application are possible during tensioning:

otherwise the descriptions of the last two types of tensioning devices would explain the same power output.

This section provides a technical vocabulary list for the concepts discussed.
Vocabulary: Heron of Alexandria, Artillery Construction, Tensioning device, Pulley system, torsion engine, belly-bow, catapult, Rudolf Schöne, Melchisédech Thévenot, axle, slider, trigger claw, capstan (small winch).