92 BEACH GRASS 



lished in 1823 defines frost-rime as "3. sort of fog 

 that appears on the surface of the sea, in severe 

 frosts, produced by the condensation of the vapor 

 arising from the water in consequence of its being 

 piuch warmer than the air." "The sea," he 

 says, ''on occasions of frost-rime is generally 

 about 20 degrees or 30 degrees warmer than the 

 air." He goes on to say, 'T was long in doubt 

 whether the freezing of the sprays and froth of 

 the waves, or the evaporation of the sea, was the 

 cause of the meteor. Having, however, taken a 

 large shallow vessel of water into the open air, 

 and placed it in a situation sheltered from the 

 wind, at a time when the frost-rime was particu- 

 larly dense, the thermometer being at zero, I ob- 

 served that this water, though perfectly still and 

 unruffled, soon began to discharge a thin vapor, 

 resembling the frost-rime, which it continued to 

 give out, until the surface was covered with ice. 

 This experiment convinced me that the cause 

 must be simply evaporation." 



The sea looks like the scene of a terrible con- 

 flagration. Great smoke-like masses of dark 

 vapor boil up, and lashed by the icy wind, roll in 



