158 Some Experiments on the Growth of Potatoes, 



At the time Mr. Knight's seedlings were planted, no other 

 object was contemplated than that of determining the respective 

 rates of increase of the varieties submitted to trial ; and therefore I 

 am unfortunately unable to speak with absolute confidence of the 

 accuracy of the rate of increase indicated by this Table. In order 

 to gain a knowledge of the weight planted, I have been obliged to 

 assume that the tubers selected for common culture weighed on 

 an average the same per tuber as those used in the actual expe- 

 riment ; but as the sample from which the tubers were in both 

 cases taken was extremely uniform, I have no reason to suppose 

 that the weight, estimated in Table B to have been planted, is mate- 

 rially at variance with accuracy. 



Table B. 



