ched by a ring, whilst the other hung in a loop over an iron
hook which formed the extremity of the shaft. The power employed to
discharge the sling was either the strength of a number of men, applied to
ropes which were attached to the short end of the shaft or lever, or the
weight of a heavy counterpoise hung from the same, and suddenly released.

[Illustration: Mediaeval Artillery Engines. Figs. 1, 2, 3, 4, 5, Chinese;
Figs. 6, 7, 8, Saracenic: the rest Frank.]

Supposing the latter force to be employed, the long end of the shaft was
drawn down by a windlass; the sling was laid forward in a wooden trough
provided for it, and charged with the shot. The counterpoise was, of
course, now aloft, and was so maintained by a detent provided with a
trigger. On pulling this, the counterpoise falls and the shaft flies
upwards drawing the sling. When a certain point is reached the loop end of
the sling releases itself from the hook, and the sling flies abroad whilst
the shot is projected in its parabolic flight.[4] To secure the most
favourable result the shot should have acquired its maximum velocity, and
should escape at an angle of about 45 deg.. The attainment of this required
certain proportions between the different dimensions of the machine and
the weight of the shot, for which, doubtless, traditional rules of thumb
existed among the mediaeval engineers.

The ordinary shot consisted of stones carefully rounded. But for these
were substituted on occasion rough stones with fuses attached,[5] pieces
of red-hot iron, pots of fused metal, or casks full of Greek fire or of
foul matter to corrupt the air of the besieged place. Thus carrion was
shot into Negropont from such engines by Mahomed II. The Cardinal
Octavian, besieging Modena in 1249, slings a dead ass into the town.
Froissart several times mentions such measures, as at the siege of Thin
l'Eveque on the Scheldt in 1340, when "the besiegers by their engines
flung dead horses and other carrion into the castle to poison the garrison
by their smell." In at least one instance the same author tells how a
living man, an unlucky messenger from the Castle of Auberoche, was caught
by the besiegers, thrust into the sling with the letters that he bore hung
round his neck, and shot into Auberoche, where he fell dead among his
horrified comrades. And Lipsius quotes from a Spanish Chronicle the story
of a virtuous youth, Pelagius, who, by order of the Tyrant Abderramin, was
shot acro