Dr. Forry on the Climate of the United States, 6fc 27 



at Port Brady to be 18<M2, while at Hancock Barracks it is 

 240-49; at Fort Sullivan it is 17°- 16, while at Forts Snellin- 

 and Howard, it is respectively 30°-83 and 24°1(), the latter being 

 partially modified bv Green Bav: at Forts Prphl* nt,-,,,™ 



and 



Constitution, and the city of Salem, the ratios are 18°-42, 16°-77 

 16° -S3 and 17°-89, and at Fort Crawford, on the other hand, it 

 is 25°-83 ; and lastly at Forts Wolcott and Trumbull, it is 14°Vl 



n 0d . . n .°' 67 ' WhUe at Council Bluffs > F °rt Armstrong, and West 



Fort Colum- 



respecti 



bus, as in the preceding comparisons, stands as an exception, its 



notwithstanding it is lower than any one in the opposite 



ratio, 



ciass, being the highest in its own, with the exception of two 

 Posts. The peculiarity in the increase of the temperature of 

 spring, as manifested in the vegetable kingdom, constitutes a fea- 

 ture which strongly characterizes excessive climates; for, as 



mboldt 



the force of vegetation, than a great heat preceded by a cold sea- 

 son." Accordingly we find that in these excessive climates, (un- 

 like the uniform ones on the ocean and lakes, in which the air is 

 moist and the changes of the seasons slow and uncertain,) summer 

 succeeds winter so rapidly that there is scarcely any spring, and 

 vernal vegetation is developed with remarkable suddenness. At 

 ort Vancouver, the difference between the mean temperature of 

 wjnter and spring is only 6°67, which is about one third of the 

 aitterence observed at the posts in our modified climates on the 

 same parallel, and little more than one fifth of the difference ex- 

 hibited in the excessive climate of Fort Snelling. 

 Another feature which characterizes these two systems of eli- 

 te remains to be considered, viz. the mean annual range of 

 the thermometer. Comparing the 



owing relations are found: — At Fort Brady, on the one hand, 

 the range is 110°, and at Hancock Barracks, on the other, it is 

 I 180 ; at Fort Sullivan it is 104°, while at Forts Snelling and 

 Howard, it i s i 19 o and 12 3o . at Forts Preble, Niagara and Con- 

 stitution, it is respectively 99°, 92° and 97°, while at Fort Craw- 

 ford, on the same parallel, it is 120° ; and lastly at Forts Wolcott 

 an d Trumbull, it is 83° and 78°, while at Council Bluffs, Fort 



foil 



posts 



West 



Fort Co- 



tabus, as before, presents an exception. In further elucidation 

 the law regulating the extremes of temperature, the four fol- 



