HOETICULTURAL SOCIETY. 101 



for I have no doubt that you are competent by tree planting to 

 effect our climate favorably. It will not be done by this genera- 

 tion, probably, but by the good old man, that your President 

 has referred to in his address, who in his dotage plants the trees 

 of which future generations will reap the reward. 



The effects of climate on organic and inorganic matter is fully 

 recognized, especially by the horticulturist, for who is more con- 

 cerned than he? The natural causes that produce the most vio- 

 lent climatic changes, and therefore, have the greatest effect up- 

 on animate and inanimate matter, are not well understood. If 

 our continent were a level unbroken plain, from the troj^ics to 

 the arctic regions, a given parallel of latitude would more nearly 

 represent the character of the climate belonging thereto. As it 

 is, when we trace the isotherms, or lines of mean temperature, 

 across our continent, we find them very eccentric in their 

 courses, apparently having but little respect for latitude. This 

 fact is most forcibly illustrated by the movements of such storms 

 as we now have under consideration and for the designation of 

 which a seemingly appropriate word, blizzard, has been coined, 

 and awaits adoption in the next edition of Webster. 



The atmospheric conditions that precede a blizzard, indeed 

 constitute the preliminary features of it, are a low barometer, 

 centered well south and moving northeasterly. As a rule, we 

 have from 8 to 15 low pressure movements during a month. Al- 

 most without exception these pass out of the territory of the 

 United States through the lower St. Lawrence valley. Just why 

 this is so need not now be considered. Usually these centres of 

 low pressure arise in the Eocky mountain regions of the United 

 States, or enter our territory from Manitoba, and, passing through 

 or near the great lakes, follow the St. Lawrence to the northeast. 

 Conditions of this kind may bring us, in the Central Mississippi 

 Valley, thunder storms, heavy rains or snow, wind, and even 

 tornadoes; but will not give us a genuine blizzard in all its fury 

 with a resultant temperature of from 15° to 30°. If, however, an 

 an area of low barometer enters the territory of the United 

 States from the Gulf of Mexico and passes northeasterly toward 

 he mouth of the St. Lawrence, and if this be during the win- 

 ter months, we may have a severe cold wave extending far 

 into the south, and borne to us in the latitude of Indiana and 

 southeasterly, by winds from the west or even the southwest. 



In some particulars the storm under consideration has excelled 

 any on record. This is especially true in regard to its extent and 



