96 LIFE IN NATURE. 



may be discerned more or less clearly a plastic 

 expanding tissue, modelled by the varying resist- 

 ances it meets. In individual instances, no observer 

 has been able to ignore this fact. " I fear," says 

 Mr. Ruskin, in a recent volume,* discussing the 

 formation of the branches of trees by fibres descend- 

 ing from the leaves " I fear the reader would have 

 no patience with me, if I asked him to examine, 

 in longitudinal section, the lines of the descending 

 currents of wood, as they eddy into the increased 

 single river. Of course, it is just what would take 

 place if two strong streams, filling each a cylindrical 

 pipe, ran together into one larger cylinder, with a 

 central rod passing up every tube. But as this 

 central rod increases, and at the same time the 

 supply of the stream from above, every added leaf 

 contributing its little current, the eddies of wood 

 about the fork become intensely curious and interest- 

 ing ; of which thus much the reader may observe 

 in a moment, by gathering a branch of any tree 

 (laburnum shows it better, I think, than most), that 



* Modern Painters, vol. v. p. 46. 



