a wind which moves in a spiral direction, as well as horizontally, which is exceedingly rapid and impetuous, but only of short duration. Of some kinds of whirlwinds the motion is slow, and they are only injurious by their vortex; while others seem to do mischief as well by their progressive as their whirling motion. Of this kind are those called typhoons, which, by their frequently following the course of rivers, seem thus also to discover their electrical origin.