TLATE V. 



Fig. 1. — Low level (Hj) section of cnleiuiii floccnli. showinj? how these floc- 

 culi appear to be made up of vertical coluuius of calcium vapor. 



Fig. 2. — High level (PL) section of the same floccnli, showing (faintly) how 

 the vapor columns seem to he bent over at the snnunit, as well as expanded. 



150 



