254 HOW CEOPS GROW. 



tirely by the roots of gorse, growing at a distance of 6 

 feet from the drain. {Jour. Roy. Ag. Soe., 1, 364.) 



In New Haven, Conn., certain wells are so obstructed by 

 the aquatic roots of the elm trees, as to require cleaning 

 out every two or three years. 



This aquatic tendency has been repeatedly observed in 

 the poplar, cypress, laurel, turnip, mangel-wurzel, and 

 grasses. 



Henrici surmised that the roots which most cultivated 

 plants send down deep into the soil, even when the latter 

 is by no means porous or inviting, are designed especially 

 to bring up water from the subsoil for the use of the plant. 

 The following experiment was devised for the purpose of 

 testing the truth of this view. On the 13th of May, 

 1862, a young rasfiberry plant, having but two leaves, 

 was transplanted into a large glass funnel filled with gar- 

 den soil, the throat of the funnel being closed with a paper 

 filter. The funnel was supported in the mouth of a large 

 glass jar, and its neck reached nearly to the bottom of the 

 latter, where it just dipped into a quantity of water. The 

 soil in the funnel was at first kept moderately moist by 

 occasional waterings. The plant remained fresh and 

 slowly grew, putting forth new leaves. After the lapse 

 of several weeks, four strong roots penetrated the filter 

 and extended down the empty funnel-neck, through which 

 they emerged, on the 21st of June, and thenceforward 

 spread rapidly in the water of the jar. From this time 

 on, the soil was not watered any more, but care was taken 

 to maintain the supply in the jar. The plant continued to 

 develope slowly ; its leaves, however, did not acquire a 

 vivid green color, but remained pale and yellowish ; they 

 did not wither until the usual time late in auturon. The 

 roots continued to grow, and filled the water more and 

 more. Near the end of December the plant had 7-8 

 leaves, and a height of 8 inches. The water-roots were 

 vigorous, very long, and beset with numerous fibrils and 



Digitized by Microsoft® 



