168 On the Selecting Power of* Plants 



tites, but consisting wholly of lime. In other respects the quan- 

 tity of earth obtained appeared to keep pace with that in which 

 the plant was supplied with it from without. Thus, the largest 

 amount of lime was from the plants that had grown in Carrara 

 marble, and of silex from those that had grown in sand. On 

 the other hand, the great increase of calcareous salts in the pro- 

 duce of the seeds that had grown up in the garden, in a soil 

 consisting of sulphate of strontian, indicates how much is owing 

 to the quantity of earthy matter brought to it by the rains. 



The following is a tabular view of the results of the above- 

 mentioned experiments : — 











Portion soluble 









Weight 



Weight 



In water. 



In nitric acid, 



Portion insoluble 

 in these men- 

 strua. 



Subject of the 

 Experiment. 



Where sown. 



of the 

 plant 

 when 



of its 

 ashes 

 when 



Consisting of 





dried. 



burnt. 



Potass com- 

 bined with 



carbonic and 

 phosphoric 

 acids. 



Same com- 

 bined with 

 carbonic and 

 phosphoric 

 acids. 



Chiefly sih'ceous. 



Lotus tetra-\ 













— 



gonolobuS) f 

 seeds 780 f 

 grs. J 







30 



5.2 



3.4 



only a trace. 



Same quanti- 

 ty of ditto. 



In a Greenhouse. 



Soil. 

 Sulphate of \ 

 strontian. j 



4002 



60 



very small. 



17.15 



not estimated. 



Ditto. 



Carrara marble. 



2233 



67.5 



1.8 



20.9 



not estimated. 



Ditto. 



Sea-sand. 



1135 



34.3 



4.1 



6.0 



not estimated. 



Ditto. 



In a Garden. 















Soil. 

 Sulphate of ) 

 strontian. j 



4862 



94.0 



0.72 



27-2 



not estimated. 



Ditto. 



Carrara marble. 



3267 



64.5 



a trace; 



28.2 



1.5 



Ditto. 



Sea-sand. 



2957 



67-0 



a trace. 



16.0 



8.8 



1660 grs.) 

 of ditto. / 



Common gar- ) 

 den mould. J 



10534 



164,50 



33.6 



27.70 



10.0 



or 

 780 grs. 



In ditto. 



5267 



82.25 



16.8 



13.85 



5.0 



In 1832 I made similar arrangements to those just alluded to* 

 with the addition of a fourth box, containing washed flowers of 



