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nurserymen call " clnmp-headed." But tiiis sort of head, so 

 desirable for picturesque purposes, may also be procured by 

 judicious treatment, as will be seen in the sequel, and with 

 sufficient room for expansion, during the youthful age of the 

 tree, and while the central shoot yet maintains its preemi- 

 nence, and the power of reaching its greatest height. 



It is pleasing to observe, in this place, how beauty and 

 utility coincide in the same object. In proportion as the tree 

 has room to expand on every side (agreeably to the foregoing 

 account of the action and reaction of the different parts on 

 one another), it must be with an equal and corresponding ex- 

 pansion of the roots. As the exposure is increased, wc uni- 

 formly perceive, that both branches and roots multiply. 

 Towards the quarter most exposed, the branches are always 

 more contracted in their growth, but in general more thickly 

 set with spray ; plainly for the purpose of furnishing a closer 

 cover of leaves, for the protection of the sap-vessels, as they 

 lie immediately under the bark. This, however, is by no 

 means inconsistent with the established fact, that a more 

 active vegetation is carried on, on the warmer than the 

 colder side of trees, and a greater deposition of nutrient mat- 

 ter consequently made on the former : Because by far the 

 largest and longest branches are always found on the warmer 

 side, though more thinly disposed over it ; and they prove 

 the superior activity of vegetation there ; while the shorter, 

 but weaker and more crowded style of ramification on the 

 colder side, shows, in like manner, its inferior activity. 

 Nevertheless, the clothing of leaves is in this way usually 

 thicker, for the wise purpose of defence from cold, on the 

 side last mentioned. 



This is extremely well illustrated, in the general develop- 

 ment of the position of branches, which we see assume all 

 the varieties of form, from the reflected, to the horizontal and 

 the upright. In all these instances it is observable that the 

 lowermost branches are parallel to the suiface of the soil on 



