7 parte superiore . . . pontis = fastened to the upper part of the bank, i.e. to the bank at a point higher up stream.—D.
9 per solum = on firm ground.
14 ab actuariis = by some light craft, lit. ‘Easily moved’ (ago).
17-18 donec . . . agerentur = So long as they were being driven on what seemed a bridge connected with the land.—C. and B. Agebantur would be more usual, but agerentur may give the reason of nihil trepidabant. Cf. donec—fecisset ll. 21-22.
19 in altum = into mid stream, usu. of the Sea.—D.
inter se = one on another, alii alios.
24 quaerendis pedetemptim vadis = feeling their way into shallow water. pedetemptim = step by step, lit. ‘stretching out the feet’ (pes + tendo). Cf. paulatim, sensim.
Reference. Polybius, iii. 46. Both Polybius and Livy thought that elephants could not swim.