METEOROLOGY OF 1 897. 
when the early darkness interferes with the observation 
at 7 P* After the water freezes in November, the tank 
is not disturbed except at the end of the month, when the 
ice IS broken and measurement made. 
EVAPORO METER. 
§22. Figure 9 represents the evaporometer which has 
been used to determine the amount of moisture used by a 
plant in Its growth. It is adapted only to small plants 
but with them serves to show the varving" demands of 
the plant from day to day. 
Fig 9. 
