MAY 261900 



A SEVERE SLEET-STORM.* 

 Hermann von Schrenk. 



During the evening and night of February 27th, a sleet- 

 storni of unusual severity occurred over a large tract of coun- 

 try including parts of Missouri, Illinois, Indiana and Ohio. 

 Sleet-storms of this kind occur with more or less regularity 

 throughout the northern United States, whenever a southern 

 storm center with rainclouds meets with freezing temperatures. 

 The falling rain is not cooled sufficiently to turn to snow, and 

 reaches the ground as rain. Here it freezes, and covers every 

 object with a layer of ice. Generally this ice layer is very 

 thin, and vanishes the next day. Occasionally, however, the 

 conditions are favorable to the formation of thick ice, and the 

 destruction which is then wrought to trees and shrubs is great. 



Accounts of such storms have appeared now and then. 

 Nipher t describes one of unusual severity which caused wide- 

 spread destruction to trees in Missouri, on the nights of Feb. 

 19th and 20th, 1882. Some six inches of rain fell at that time. 

 He says of this storm: " The enormous loading of the trees 

 resulted in immense destruction of fruit and ornamental 

 trees. * * * At Pleasant Hill, the weighing of ice- 

 covered branches led to the result that a cedar tree 10 ft. 

 high and with branches spreading at the base, had received 

 over four hundred pounds of ice. * * * The damage 

 occurred over an area of almost 5,000 square miles." 



In Europe these ice-storms are apparently not as common 

 as with us. Fischer X mentions a number of notable storms 

 which occurred in the Harz mountains from 1827-1875. He 

 states that the weight of ice on the trees is often fifty pounds 

 on six pounds of wood. A spruce tree 3^ ft. high had to 

 support 165 lbs. Jamin§ describes a most extensive storm 



* Presented in abstract to The Academy of Science of St. Louis, April 2, 

 1900. 



t Nipher, P. E. Trans. St. Louis Acad, of Science. 4 : lxxii. 1882. 



% Fischer, W. R., in Schlich's Manual of Forestry. 4: 493. 1895. 



§ Jamin, J. Le Verglas du 23 Janvier. Revue des Deux Mondes. 31 : 922. 



Feb. 15, 1879. 



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