FUNCTION IN PLANT LIFE 29 



membrane d, and may be designed to facilitate induction 

 between the conducting layer and the seed substance, 

 inasmuch as the latter, unlike the horse-chestnut, is not 

 adherent to the inner insulating membrane b, except at 

 this point. Two considerations at least present them- 

 selves. Capacity in the case of vegetables and fruits is 

 governed by the nature and quantity of the conducting 

 liquid as well as by the specific inductive capacity of the 

 dielectric, and the area of the respective plates or discs or 

 membranes and their distance from each other ; and upon 

 capacity plus absolute insulation the life of the vegetable 

 or fruit depends. In the horse-chestnut assuming specific 

 inductive capacity and absolute insulation to be the same 

 in both we have the plates of comparatively large area 

 and close together, but with very little moisture. In the 

 edible chestnut one of the conducting surfaces, i.e., the 

 seed substance, is irregularly shaped, is removed in youth 

 except at the posterior part of j from the membrane b, 

 but contains a large quantity of moisture ; is, in fact, 

 surcharged. Actual test showed the tension of the seed 

 substance to be higher than that of the horse-chestnut, and 

 this would be in accordance with established laws.* But 

 what is the purpose underlying it ? 



I may be wrong, but a possible explanation presents 

 itself. 



Let us suppose that the horse-chestnut seed, not being 

 intended for food, is destined only to ripen, to fall from the 

 tree and pod, and to be buried in the earth to reproduce its 

 species. That would seem to be the sole object of its 

 creation, and nothing but the perfection of its insulation 

 would equip it with a sufficiently robust constitution to 

 enable it to survive prolonged exposure under conditions 

 unfavourable to germination. 



* See chapter on INDUCTIVE CAPACITY. 



