know by heart also with absolute accuracy the huge and complicated
works of the Sanscrit grammarians.

H. 4.--Caesar further tells us that the Druids taught the doctrine of
transmigration of souls, and that their course of education included
astronomy, geography, physics, and theology. The attributes of their
chief God corresponded, in his view, with those of the Roman Mercury.
Of the minor divinities, one, like Apollo, was the patron of healing;
a second, like Minerva, presided over craft-work; a third, like
Jupiter, was King of Heaven, and a fourth, like Mars, was the
War-god.[55] Their calendar was constructed on the principle that each
night belongs to the day before it (not to that after it, as was
the theory amongst the Mediterranean nations), and they reckoned
all periods of time by nights, not days, as we still do in the word
"fortnight." For this practice they gave the mystical reason that the
Celtic races were the Children of Darkness. At periods of national
or private distress, human sacrifices were in vogue amongst them,
sometimes on a vast scale. "They have images [_simulacra_] of huge
size, whose limbs when enclosed [_contexta_] with wattles, they fill
with living men. The wattles are fired and the men perish amid the
hedge of flame [_circumventi flamma exanimantur homines_]." It
is usually supposed that these _simulacra_ were hollow idols of
basket-work. But such would require to be constructed on an incredible
scale for their limbs to be filled with men; and it is much more
probable that they were spaces traced out upon the ground (like the
Giant on the hill above Cerne Abbas in Dorset), and hedged in with the
wattles to be fired.

H. 5.--From the historian Diodorus Siculus, whose life overlapped
Caesar's, we learn that Druid was a native British name. "There are