74 REPORT ON THE STATE CABINET. 



But to this rule there are certain exceptions. It makes a great differ- 

 ence whether the ascent be steep or gradual. The position of the surface 

 from which the ascent is made, is also important in its influence. Tlie 

 average temperature in the Great Salt Lake valley in our own continent, 

 though it is four to five thousand (4,351) feet above the level of the sea, 

 is as warm as the places on the California coast in the same latitude and 

 at the sea level, as Fort Humboldt, for example ; Fort Madison, Iowa ; 

 and Ottawa, Illinois : the average for the year in Great Salt Lake City 

 being about 52 ; that at Fort Humboldt is given at 52.1 ; Fort Arm- 

 strong, 50.3 ; and Ottawa the same. 



Again: the cereals, as barley, etc., will grow on the north side of the 

 Himalayas at an elevation of some two or three thousand feet higher 

 than on the south side, notwithstanding a difference of some two degrees 

 in latitude. But on the south side, the reflected rays of the sun are sent 

 up from a plain which is nearly on a level with the sea ; while on the 

 north side, the reflecting surface is the elevated plateau and table land 

 of Thibet. 



In apparent contradiction to this law, we often find the weather much 

 colder in low narrow valleys, especially in autumn and winter. I have 

 known the thermometer to iall eight degrees in a descent of some two 

 hundred feet, and at a distance of not more than half a mile ; and all 

 persons have doubtless observed the fact that frosts frequently cut off the 

 tender crops much earlier in the low lands than on the hill-sides and 

 hill-tops even adjoining them. The reason is, doubtless, to be found in 

 the fact that the cold air being heavier than warm, descends into the 

 valleys by the force of its own weight. This phenomenon, therefore, can 

 occur only when the stratum of air is colder than the earth below it. 



III. Distance from the Sea Coast. 



Inland distance, or distance from the sea coast, is an important element 

 in determining temperature. 



Perhaps this fact will make no great difierence in the general average 

 for the year. Its influence is chiefly felt in the contrasts between summer 

 and winter, and the heat of the day when compared with the coolness 

 of the night. 



The following examples will illustrate this principle : 



