TLATE V. 



Fio. 1. Low level (Hi) section of calcium fiocculi. showing bow these floc- 



culi appear to l)e made up of vertical colunuis of calcium vapor. 



Fig. 2. High level (IIJ section of the same Hocculi, showing (faintly) how 



the vapor columns seem to be bent over at the summit, as well as expanded. 



150 



