MEASUREMENT OF GROWTH BY WEIGHT 



293 



as the slips of paper are of the same size as those of the thermo- 

 graph, the temperature curve may be transferred directly to them 

 or to the sheet containing the plotted curve. 



371. Measurement of Growth by Weight. Measurement of the 

 growth by weight may be undertaken successfully only in mas- 

 sive organs, in which the interchange between the organ and the 

 atmosphere in the form of gases and watery vapors is at a mini- 

 mum, and hence this method may be used with profit only in 

 estimating the increase of large fruits. Cultivate some vigorous 



Fig. 140. Showing method of arranging a fleshy fruit on pan of Anderson auto- 

 matic registration balance. Accretions in weight are equalized by weights dropped 

 in the opposite pan of the balance, and a record is made by a pen tracing. 



variety of squash, watermelon, or any cucurbit with a large fruit, 

 and train the vines so that the branch bearing a young fruit may 

 be carried to a registering balance, or if this is not available, to 

 some form of weighing apparatus sensitive to half a gram, and 

 with a capacity of 10 kilograms. The fruit must be adjusted so 

 that its full weight is carried on the scale pan, and the branch to 

 which it is attached bends freely to allow the action of the bal- 

 ance. If a registering balance is used it will need but little atten- 

 tion, but should be adjusted at least once daily. If an ordinary 



