RAYMUND SANGER 
Fig. 1—Conieal center of the hailstone 57.7; 
= 
real length of the figure, 2.2 cm 
Fic. 2—Cross-section of center of hailstone 57.7 (polarized light); real length of 
the figure 
an advanced stage of development that the 
original particle, namely, a snow crystal, can 
now only just be recognized. 
In conclusion, a remarkable finding should be 
mentioned, which has already resulted from in- 
vestigations made with the Hail Research Wind 
Tunnel. It appears that large ice particles, which 
contain imprisoned within themselves consider- 
able quantities of still liquid water, can be pro- 
duced relatively easily by coalescence with sub- 
, 22 cm 
cooled droplets. This immediately raises the 
question, whether the bigger natural hailstones 
could not also carry enclosures of water. This 
possibility would allow us to understand how 
growth may take place in a considerably shorter 
time than is generally assumed nowadays. In 
order to find out, investigations would have to 
be carried out immediately after the hailstones 
had fallen, and might therefore prove especially 
difficult. For there can be no question of pre- 
