~ 
90 Abstraction ‘of Nitrogen from the Atmosphere. 
at the period of the most modern deposition of salt, and they 
are hich suc- 
of the earlier geologists. Of late, tic. subject has been taker 
up by Sir Alexander Crichton, who has published a very in- 
teresting memoir in the Annals of Philosophy for February 
and March, 1825. Its title is, ““@g the Climate ofthecAude~ 
dilavian World, and its independence vf Go}ay; 
* Captain Parry, in his third voyage, found them as high as between the 
73d and 74th degrees north latitude, 
t Of Pennsylvania. 
