366 What are Animals and Plants ? 



equilateral triangle, each side of which is twelve hun- 

 dred miles long, and that other vast regions of the earth's 

 surface are, like it, clothed not only with herbage, but with 

 teeming vegetable produce of all kinds and dimensions. 



Now, if we suppose two-thirds of the earth's dry land to 

 be clothed with only such vegetation as may be estimated to 

 produce an average increase of its substance, amounting to 

 but one three hundred and sixty-fifth part of an inch daily, 

 then we should have freshly formed each year as much 

 vegetal matter as would constitute a cube fifteen miles in ex- 

 tent in each of such cube's three dimensions ! 



IX. But living creatures not only grow and develop their 

 own bodies ; they also reproduce their kind ; and this is again 

 an action to which there is nothing comparable or analogous 

 in the whole inorganic world. 



Thus every living being may be said to be a creature pos- 

 sessing an innate tendency to undergo a definite cycle of 

 changes when exposed to certain fixed conditions; that is, 

 when supplied with an adequate amount of temperature, 

 moisture, suitable gaseous matter, food, etc. Inorganic and 

 dead substances may tend to undergo a series of changes, but 

 such series never constitutes a ' cycle ' — i.e., a series returning 

 to the point whence it set out. We see such a cycle of 

 changes in the ^gg, the chick, the fowl, and the ^gg again ; 

 or the ^gg, the grub, the chrysaHs, the butterfly, and ulti- 

 mately its ^gg\ or the seed, the young plant, the mature 

 plant, the flower, the fruit, and the seed again. 



Inorganic substances tend simply to persist as they are, 

 and have no definite relations either to the past or to the 

 future. AVhence it comes, or what it has been or shall be, is 

 nothing to its present being — which is its only being. But 

 every living creature, at every step of its life, regards both 

 the past and the future, and thus lives continually in a 

 definite relation to both these as well as to the present. 



