43 



Volume Increase in Swelling Seeds, 



Since all seeds which take up water experience a change in 

 volume, experiments were conducted to determine this change. A 

 priori it appears self-evident, that with the taking up of a 

 certain amount of water by a body capable of increasing, a cor- 

 responding volume increase must result. Persons who have made 

 observations differ in their conclusions. Some like Payen, 

 maintain that the weight of the absorbed water really exceeded 

 the increase in volume of the seeds. Wiesner and others believe 

 that a condensation takes place in the seed when water is taken 

 up. Wiesner has determined by means of a series of well conduc- 

 ted investigations, that heat developes in soaking seeds, ear- 

 lier than carbon dioxide is formed. From these facts Wiesner 

 concludes that the increase of heat in seeds taking up water, 

 results from a condensation of the water in the tissue of the 

 seeds and a liberation of heat follows. Heat increases rapidly 

 at first but later carbon dioxide being produced, the heat ceas 

 es to increase farther, 



I used one hundred fifty grams each of Perry's Golden Eagle 

 corn, Ferry's Large White Marrowfat peas, Lupinus luteus, Phas- 

 eolus multiflorus, and Phaseolus vulgaris. Each kind of seed 

 was placed in a large bottle filled with water, and immediate- 

 ly closed by an absolutely close fitting cork from which extend 

 ed vertically, a long glass tube having an inside diameter of 



