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NOTICES OF AUTHORS, 



frozen so hard as to require a hatchet to dissect 

 them, and revising on thawing, it will he found that 

 the fluids were principally oleaginous, which do not 

 expand in congealing; and in the case of insects heing 

 frozen in masses during the night, and resuming- 

 their liveliness next day in the sun, we think, if their 

 fluids have congealed at all, that either the vessels 

 must have yielded, being elastic (which might more 

 likely take place in a small body, T^dthout general 

 fracture and derangement) ^ or that the fluids had not 

 extended by being congealed ; but it is very pro- 

 bable, though frozen together in a mass of water 

 and mud, that their fluids, from being of an acid 

 nature, had resisted the congelation. 



With regard to trees, we have heard that intense 

 frost often splits the trunks of some of our indige- 

 nous kinds by congelation * ; but these trees re- 

 tain vitality, and only suffer from the consequences 

 which may ensue from the fissures. We have 

 seen evergreens, plants from milder climates, and 

 trees which had not thoroughly ripened their 



* Is the rending of the stems of trees, during intense frost, in° 

 ternal only, and occasioned hy the alburnum expanding more by 

 congelation than the drier matm'e wood ? or, is it external, antf 

 caused by the contractile effect of the dry air and cold on the al- 

 bui'num rendering it insufficient to surround the mature wood, 

 which, from dryness and want of livin? susceptibility, may non 

 contract so much 



