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NOTICES OF AUTHORS. 



ber will still be of a quality not inferior to what 

 would take place in its natui'al state ; or, in other 

 words, it will correspond with that degree of quali- 

 ty and quantity of timber, which the natui'e and 

 species of the tree admit of being produced. If the 

 tree be in its natural state, the annual increase of 

 timber occasioned by priming, must necessarily in- 

 jure its quality in a degree corresponding with the 

 increased quantity. If the tree be in a better cli- 

 mate and soil than that which is natural to it, and 

 at the same time the annual increase of wood be pro- 

 moted by pruning, it is evident that such wood must 

 be of a i^ery different quality from that produced in 

 its natural state (that is X)ery infeiior)^ — " What- 

 ever tends to increase the ivood in a greater de- 

 gree than what is natural to the species ivhen in 

 its natural state, must injure the quality of tlie tim- 

 ber. Pruning tends to increase this in a consider- 

 able degree, and therefore it must be a perjiicious 

 practice'' — " Mr Knight has shown, in a very strik- 

 ing manner, that timber is produced, or rather that 

 the alburnum or sap-wood is rendered ligneous, by 

 the motion of the tree, during the descent of the 

 tree (or proper) sap. It is also sufficiently known, 

 that the solid texture of the wood greatly depends 

 upon the quantity of sap which must necessarily 



