65 OF THE SAP, 



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in the autumn, when, seemingly from the in- 

 creasing cold, they become benumbed ; and 

 he explains it by supposing a greater degree 

 of electricity in the air at the former season. 

 Dr. Brown s hypothesis, of their irritability 

 being as it were accumulated during winter, 

 offers a much better solution, either with re- 

 spect to the animal or vegetable constitution. 

 For the same reason, it is necessary to apply 

 warmth very slowly and carefully to persons 

 frozen, or even chilled only, by a more than 

 usual degree of cold, which renders them 

 more susceptible of heat, and a temperate 

 diet and very moderate stimulants are most 

 safe and useful to the unexhausted constitu- 

 tions of children. The same principle ac- 

 counts for the occasional flowing of the sap in 

 autumn after a slight frost. Such a prema- 

 ture cold increases the sensibility of the plant 

 to any warmth that may follow, and produces, 

 in a degree, the same state of its constitution 

 as exists after the longer and severer cold of 

 winter. Let me be allowed a further illustra- 

 tion from the animal kingdom. Every body 

 conversant with labouring cattle must have 

 observed how much sooner they are exhaust- 



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