298 Observations upon the effects of Frost, 



Register of Geothermometers in the Garden of the Horticultural Society 

 in the month of January, 1838. 





1 foot deep. 



2 feet deep. 





1 foot deep 



2 feet deep. 





46 



46 



January 17 



34 





2 



46 



46 



18 



34 



37* 



3 



45 



46 



19 



331 



31 



4 



42 



43 



20 



33 



37 





42 



44 



21 



33 



35 





41 



44 



22 



33 



35 



7 



40 



43 



23 





36 



8 



39 



41 



24 



33 



36 





37 



41 



25 



33 





ib 



36 



40 



26 



33 



35 



H 



36 



40 



27 



33 



35 



12 



36 



40 



28 



33 



35 



13 



35 





29 



33 



35 



14 





39 



30 



33 



36 



15 



34ft 



38 



31 



33 



35£ 



16 



34 



38 









It will doubtless have been remarked, that in the previous obser- 

 vations, it has been assumed that the destruction which took place 

 among plants was owing to the intensity of the cold on the morning 

 of the 20th of January. I am aware, that in the opinion of some 

 intelligent observers, it was not so much the excess of cold which 

 produced death, as the subsequent thaw, either on the 22nd of Ja- 

 nuary, when the thermometer rose to 46°, or in the end of the 

 month, and in February. This opinion seems to be formed upon 

 the absence of any appearance of death in some cases till that time, 

 and, also upon the well known fact, that frozen vegetables and 

 trees, suddenly thawed, will die, while they recover, if the temperature 

 is raised by slow degrees. The absence of the appearance of death 

 in certain plants, till some time after it actually takes place, is per- 

 haps owing to the decomposition, which is induced by the inten- 

 sity of cold, either being suspended so long as they remain 

 frozen, or proceeding very slowly in cold weather. That it really 

 was the excessive cold, which in general produced destruction, 

 may be concluded from this; that such effects as we experienced 



