294 TRANSACTIONS OF THE NORTHERN 



trou2;h of the Rocky Mountains, through these waves, pass in their 

 eastward route, in heavy westerly gales. The annual invasion occurs 

 in October and continues until January, and accounts for the severe 

 cold of this latitude, and other localities of the Northwest, within the 

 track of this invader. 



We have an "atmospheric wave " during the spring, summer, and 

 first autumn month, similar, but in a greatly modified form. It is cer- 

 tain to roll over us in April, May, and June, and often in July, and 

 almost certainly does it make its appearance the last week in August, 

 and never fails to appear in September. During twenty years' observa- 

 tion, this ugly visitor has rarely failed to put in an appearance, when 

 visits of the kind would exert the most baneful influence. We are 

 often witnesses of these atmospheric waves, and are led to exclaim 

 that our location upon these parallels of latitude is quite inopportune ; 

 this is true. The changes may always be expected, and could only be 

 remedied by interposing large belts of timber at near intervals across 

 the track of the unwelcome visitant. 



This atmospheric wave may be anticipated many days, in its ap- 

 pearance, and every careful provision made to meet the onslaught of 

 this cold wave. As casual phenomena, we have, during the month of 

 August and November, shooting stars. This demonstration of the 

 heavenly bodies is quite regular in its occurrence. Parhelia, sun-dogs, 

 are attendants upon the sun in cold weather, and this phenomena is a 

 good cold weather indication. 



PROTECTION AND PLANTING OF FOREST TREES. 



BY DR. A. G. HUMPHREY, GALESBURG. 



To us who have been pioneers of our prairie state, and who have 

 for years borne the cold blasts of winter, and the scorching heat and 

 parching drouths of summer, our subject is fraught with intense 

 interest. 



The reasons for protecting the forests we already have, and "for 

 covering our treeless ocean-like prairies with deciduous and coniferous 

 forests, are varied and important. 



It is fairly estimated that if every tenth acre was covered with forests, 

 it would decrease the average heats of summer six or eight degrees, and 

 reduce the colds of winter equally as much or more. It is also ascer- 

 tained that in addition to producing a very much milder and more 

 equable climate, the effect of these forests would be most beneficial in 

 the production of crops, as materially tending to attract rain and to re- 

 tain moisture in the ground, and thereby causing the grasses and cereals 

 to grow more vigorously and certainly. Forests in timber belts for wind 

 breaks keep off the early fall and late spring frost, which often prove so 

 destructive to our fruit interests. 



Without their shade, shelter, and ameliorating climatic influence, the 

 culture of the apple, the peach, plum or apricot, is exceedingly unrelia- 

 ble and indeed hardly possible. 



