74 TREE PLANTER'S MANUAL. 



water thus evolved through the vegetable and animal economics, is yet un- 

 known. The phenomenon invites the chemist and the forester. Mean- 

 while we must content ourselves with this fact, that, given the moisture, 

 we have the forests; given the forests, we have the moisture increased. 



When we "learn to heart" what chemistry teaches, that the forest equal- 

 izes the temperature and moisture, and that its roots, leaves and other tis- 

 sues are nature's great retort in which the gases are distilled, we also learn 

 what an unpardonable crime it is to wantonly destroy the forests. 



CLIMATIC. 



COSMIC AND LOCAL FACTORS. 



"The climate of a country," says Humboldt, "is the combination of calor- 

 ific, aqueous, luminous, serial, electrical and other phenomena, which fix 

 upon a country a definite meteorological character that may be different 

 from that of another country under the same latitude and with the same 

 geological conditions." 



Cosmic factors are based upon certain fixed principles, such as the in- 

 clination of the earth's axis to the plane of the ecliptic, which causes ther- 

 mal variability; the position of the sun in the heavens in its annual swing 

 between the tropics, which contributes to the same result; the circumferen- 

 tial velocity of the earth on its different parallels, lessening proportional to 

 distance from the equator, which produces differences of wind-waves that 

 directly play into meteorological phenomena; the relative position of land 

 to water areas, having unlike heat capacities which, in turn, give direction 

 and force to air and sea-currents; the elevation, the latitude, the configura- 

 tion of a country, which with other co-factors are directly concerned in the 

 make-up of climate, before whose fiat must we bow and acknowledge our 

 utter weakness. 



OUR SITUATION. 



Minnesota extends from north latitude 43 degrees 50 minutes to 49 de- 

 grees, and from 89 degrees 29 minutes to 97 degrees 5 minutes west longi- 

 tude. It is therefore central in the North American continent, midway 



