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of toxic influences. Freezing breaks up the bark 

 and wood cells, allowing it to dry very rapidly, 

 probably before sap could move in a natural cur- 

 rent. The human race is continually eating tons 

 and tons of frozen fruit with impunity; every 

 perennial plant from the grass in our yards to the 

 largest forest trees habitually survive frosting; 

 apricots, peaches, pears, plums, in fact all well 

 known orchard trees are pruned in such cases, not 

 to remove poisonous branches, but unsightly wood ; 

 and who has not seen healthy oranges and lemons 

 sprout right up through dead, frozen tops? 



The great susceptibility of fig trees to be injured 

 in the South, the fact that they often show more 

 resistance to cold at one time than at another, dif- 

 ferent parts of the same tree not being affected uni- 

 formly, indicate various results at one place that 

 do not occur at another, as explained by Candolle's 

 laws of temperature formulated many years ago : 



1. All other things being equal, the power of 

 each plant, and of each part of a plant, to resist 

 extremes of temperatures, is in the inverse ratio of 

 the quantity of water they contain. 



2. The powder of plants to resist extremes of 

 temperature is directly in proportion to the viscid- 

 ity of their fluids. 



3. The power of plants to resist cold is in the 

 inverse ratio of the rapidity with which their fluids 

 circulate. 



