146 



Trans. Acad. Sci. of St. Louis. 



under side ; the drops froze and formed long icicles, often one 

 for every inch. Under this weight the branches drooped more 

 and more; the strongest branches were bent to the ground, 

 and in many instances the weight was great enough to break 

 the branch. The smaller branches where the weight of ice 

 was proportionately greatest often pointed vertically down to 

 the ground. The rows of icicles then were almost horizontal. 

 Adjacent branches came to touch their neighbors and in a 

 short time a mass of ice joined them one to the other. 

 By moving one branch one could move the whole tree, one 

 way or the other, as if it were one solid piece. This was 

 particularly true of the conifers, where the opportunity for 

 forming a solid coating of ice was so much more favorable. 

 Such an ice-coated tree, when moved by the wind, moves as 

 a mass, and breaks with incomparably greater ease than a 

 tree in which each branch acts for itself, and can give way 

 before the wind pressure. 



Trees. 



Acer dasycarpum. 



Ulnius Americana. 



Malva sp. 



Malva " 



Peach (Prunus persica) 



it 

 <« 



Platanus occideutalis. 

 Thuja occidentalis. . .. 

 Pinus austriaca 



Viburnum 

 n 



sp. 



Pinus Btrobus. 



A. 



Branch 



with ice 



Grams. 



Tsuga canadensis. 

 it « 



132 



116 



52 



206 



2121 



374 



420 



307 



69 



35 



20 



1322 



1540 



285 



325 



608 



610 



275 



65 



55 



19 



154 



316 



145 



755 



1120 



B. 



Branch 

 without 



ice. 

 Grams. 



17.5 



4.5 



5.5 

 24 

 157 

 48 

 26 

 37.5 



2 



2.5 



2 

 98 

 108 

 18 

 23 

 35 

 27 

 18 



5 



8 



3.5 



6 

 22 



7 

 22 

 33 



Remarks. 



With icicles. 



With icicles. 



With icicles. 

 Upright branch. 

 With icicles. 



Larger branch. 

 Larger branch. 

 With icicles. 



With icicles. 



