6 



LETTERS ON TREES. 



or on which the seed dropt from which they sprang, 

 continuing year after year, and from age to age, to be 

 seen and read of all men living near them, — and many 

 of them, in all parts of the world, allowed to live on 

 and grow without let or hindrance, one would think 

 that nothing were by this time better or more famili- 

 arly known than the natural age and size of trees. 



11. It may very confidently be affirmed, however, 

 that on the assumption stated as to the nature of trees, 

 — to wit, that every individual tree is an individual 

 plant, nothing definite or satisfactory has yet been 

 ascertained respecting either the natural longevity or 

 the natural size of any one species of tree — a circum- 

 stance which contrasts remarkably with the precision 

 of our knowledge, as far as it goes, as to these parti- 

 culars in the case of animals, and all the more from 

 the facihties which thus obviously obtain for making 

 observations upon trees. Nay, more, there are many 

 known facts in regard to trees which, on that assump- 

 tion, it is difficult or impossible to reconcile with the 

 principle of their subjection to the laws of a limited 

 duration of life, and of a limited size of organism. 



12. But what if that assumption be a wrong one ? 

 What if trees be not what they seem to be, and what 

 most persons take them to be ? The common notion, 

 as we have seen, is, that a tree is an individual in the 

 same sense that a dog or a horse is, and it certainly 

 appears to be such. It is assumed that the trunk, and 



