THE BOOTS 25 



may easily learn in " weeding " a flower or garden 

 bed. Try to uproot another specimen by pulling 

 sidewise on the stem, and it will be found even more 

 difficult to accomplish. Now tie a strong cord 

 around the stem of a third specimen, and pass the 

 cord over a thick branch of a tree or the top of a 

 fence. Tie weights or heavy objects to the free 

 end of the cord, and add to them until the plant 

 is torn from the ground. How many pounds were 

 necessary to do this ? If a strong pair of spring 

 scales are at hand, this experiment may be per- 

 formed more exactly. Tie the hook of the instru- 

 ment to the upper part of the stem of a tomato 

 or other small plant, and pull directly upward. Note 

 the number of pounds indicated by the scale as the 

 plant is torn loose. The plant is seen to come away 

 with a mass of earth adhering to the roots. The 

 roots are very plainly organs of fixation, and not 

 only penetrate the soil, but clamp a large mass so 

 that they may not be easily torn up. These organs 

 anchor stems so securely that very heavy action of 

 wind, water, or of animals is necessary to displace 

 them. In a walk through a forest in which trees 

 have been uprooted by storms, note the manner 

 in which the masses of earth are clamped by the 



