Plate 48.
THUNDER-CLOUDS FORMING.
In Plate 49 we have on the left hand a specimen in which the outspreading is just beginning, and the same cloud is shown half an hour later on the left of plate [50]. A complete cumulo-nimbus in full work is shown on the right of Plate 49, and the same appears on the right in Plate 50.
Plate 49.
THUNDER-CLOUDS.
(Cumulo-nimbus.)
Plate 49.