SECTION III. 



395 



because the wounded part of the head will imbibe the air at every ori- 

 fice, to the great prejudice of the tree. 



" Besides this, if we pay any regard to the doctrine of the circulating 

 of the juices in plants, we must allow that the heads of the trees are 

 equallj/ useful to nourish the roots, as the roots are to the heads ; so that, 

 if there is a waste of sap both at the top and bottom of the trees, it 

 must weaken them in proportion. For whoever will be at the trouble 

 to try the experiment on two trees of equal age and health, and cut the 

 branches off from one, and leave them upon the other at the time of 

 transplanting, if the latter is well secured from blowing down, it will 

 be found to succeed much letter than the other. Or, if the same thing is 

 practised upon two trees left standing, the tree, whose branches are cut 

 off, will not mahe half the progress as the other, nor will the stem in- 

 crease in its bulk half so fast. Therefore, where trees are transplanted 

 young, there will be no necessity for using this unnatural amputation, 

 and the success of these plantations will always give pleasure to the 

 owner." — Gardener's and Botanisfs Diction, in voc. Planting." 



I have particular satisfaction in quoting these sentiments from the 

 great work of Miller, and I have little doubt of their being perused with 

 equal satisfaction by the discerning reader. In fact, no advocate of the 

 system which is attempted to be established in this Essay, could have 

 given this material part of its principles with greater force and truth. 

 It clearly shows that, if arboricultural science, in respect to this art, 

 had not been stationary/ for a century in England, the giving immediate 

 effect to wood, instead of being, as it now is, a rude and uncertain practice, 

 would long since have risen to the rank of a regular art, justly esteemed, 

 and as generally cultivated. 



Note III. Page 63. 



According to the best late phytologists, water is an agent as necessary 

 to the development of vegetable life, as it seems to be a constituent of 

 vegetable organisation. A dry seed does not act on the surrounding air, 

 until it has imbibed water. Water is likewise the vehicle by which 

 nutrient matter is carried into plants, and in the opinion of some, is 

 even reduced in them to a solid form, and applied to the purposes of 

 nutrition. See Ellis, Veget. Physiol, in Suppl. Encyclop. Britan. 



Notwithstanding what is here said in the text, respecting light as a 

 condition of internal development peculiar to plants, it may be doubted 

 whether it be not nearly as necessary to animals. Cattle will not 

 fatten so wellj when stall-fed or shut up, as on good ground, and in 

 fine weather, with the free enjoyment of light. Light is caloric ; and 



