262 



could iKtt liiid aii\- statement to that elTect in the authors 

 mentioned. They say that hij;- eiaeks can be produced 

 in trees as a eouseiiuence ol" tlie foiiuation of ice in tlieir 

 intei'ior l)ut their theory of death is entirely dilTerent and 

 will be ex])laine(l later. 



Accordinu" to Senebier (ISOO) ice miulit cause death 

 l)y its ex))ansioii. 



But soon several investigators showed that tlie ctdls 

 are not broken by freeziu^-. Goepjx'il (18l>0) says that 

 the large cells of Calla ctJiiopica do uot show, w^heu their 

 sap is couuoaled, any expansion of the cell wall observ- 

 able under the niicroscoi)e. lie furthermore states that 

 in the lim)) tissue, after thawiui-', the cellular structure 

 remains intact and that the cell walls are never torn. 



]\Iorren (1853) confirmed the obs<'rvation that there is 

 no evidence of ruptured walls. 



Xageli (1860) calculated what should be the expansion 

 of a cell during the formation of ice in it and showe<l that 

 this expansion is never great enough to break the cells, 

 the membranes of which are always sufficiently expan- 

 sible. Besides, he observed that often the cells in con- 

 tact with the intercellular masses of ice are actually not 

 damaged. 



Schacht ( 1854) noted that the juice exuded from pota- 

 toes after freezing does not contain starch and he con- 

 cluded from that observation that the cells could not be 

 lacerated. 



Prillieux (18()5)), after describing the formation of ice 

 in the intercellulars, states that ice may tear the tissues 

 but never the cells and that there is no necessity of as- 

 suming that the membranes are torn to explain that the 

 juices come out of the cells. 



To summarize : The opinion that ice bursts the cells as 

 it would a bottle has been advanced by some early biolo- 

 gists. Between 18,')() and 1870 several authors demon- 

 strated that it is not based on exj)erimental and ob- 

 servational ('\i(leiice. From the Ix'giiiniiig <>f the ])res- 



