Dick Sands the Boy Captain by Jules Verne — Read

The storm had now burst in full fury, and fortunate it was that a refuge had been found. The rain did not fall in separate drops as in temperate zones, but descended like the waters of a cataract, in one solid and compact mass, in a way that could only suggest the outpour of some vast aerial basin containing the waters of an entire ocean. Contrary, too, to the storms of higher latitudes, of which the duration seems ordinarily to be in inverse ratio to their violence, these African tempests, whatever their magnitude, often last for whole days, furrowing the soil into deep ravines, changing plains to lakes and brooks to torrents, and causing rivers to overflow and cover vast districts with their inundations. It is hard to understand whence such volumes of vapour and electric fluid can accumulate. The earth, upon these occasions, might almost seem to be carried back to the remote period which has been called "the diluvian age."

Happily, the walls of the ant-hill were very thick; no beaver-hut formed of pounded earth could be more perfectly water-tight, and a torrent might have passed over it without a particle of moisture making its way through its substance.