THE OAK. 11 



quantity of matter is given whereof it is to be composed. 

 Upon this model, therefore, on the 25th of August, 1759, 

 Mr. Sineaton completed his lighthouse, being the third 

 structure of the kind which had been raised on the 

 dangerous rock from which it derives its name." How 

 wisely he acted in choosing Nature for his instructress 

 may be inferred from the fact that it has now stood 

 upwards of a hundred years, without requiring any essen- 

 tial repairs. 



The trunk of the Oak, thus perfectly adapted as it is by 

 its form to resist the most violent action of the wind, 

 derives additional strength from the slow rate of growth 

 of its timber. A very small quantity of woody fibre is 

 deposited every year, but it is proportionately dense and 

 solid, and the concentric annual layers are very firmly 

 united. Hence it is admirably prepared to withstand 

 lateral violence, as well as to support its enormous super- 

 incumbent weight of branches ; while its tap-root, de- 

 scending perpendicularly to a great depth, and its tortuous 

 underground arms proceeding horizontally at a greater 

 depth beneath the surface than those of most other trees, 

 are equally efficacious in resisting any upheaving force to 

 which its spreading and abundant foliage might otherwise 

 render it peculiarly liable. 



Were it not for this wonderfully massive structure of 

 the main trunk, the Oak would be unable to bear up the 

 ponderous weight of its enormous limbs, which, each a 

 mighty tree in itself, would rend in pieces any less sub- 

 stantial support. For it must have been remarked by 

 every one who has looked thoughtfully on a full-grown 

 Oak, that the trunk does not divide into several smaller 

 ones, all approaching to a perpendicular direction; but 

 that its unwieldy arms quit the bole almost horizontally, 

 so that the centre of gravity of each lies a long way with- 

 out the base of the tree, and is therefore constantly 

 exerting its utmost power to tear itself away from the 

 central column. This tendency to preserve a horizontal 



