ROOTS 71 



aiifl invariably seeks tlie lii^Mit aiul L^^rows upwards. 

 This can be proved by ^rowinj^ some mustard seeds 

 on a piece of flannel about the size of a shillinj^, 

 floating it on water in a saucer exposed to lii^ht 

 from a sini^le window; as soon as the lea\es appear, 

 the)- will lean towards the liL,dit, whilst the roots 

 will point tf)wards the dark part of the room. 

 If a "germinating seed is even placed with the 

 root up|)ermost, and the plumule [jointing down- 

 wards, it will \ery speerlil}' riL;ht itself, the stem 

 will turn and i^row up. and the root will seek 

 the L^round. 



The amazini^" strenLjth of i^row iiii^" tree roots can 

 be imagined when we watch a tree in full leaf 

 during a high wind. As the terrific force of the 

 gale swa\s the trunk backw ards and forwards the 

 roots are subjecterl to an enormous strain. Like 

 great india-rubber cables the)' give and retract, and 

 when the wind subsides we find the trunk as rigid 

 as ever. 



If my readers will seek for the specimens 

 enumerated below, and compare them with the 

 remarks made in this chapter, thc\' will have such 

 a general idea of the functions of roots as will, I 



