FOREST EXPLOiTAflOtf. 119 



in order to ensure the full benefits of this method of forest 

 management being secured. 



If by a tentative process, based on superficial extent, as 

 it necessarily must be, modified in accordance with the 

 number of trees, and with the cubic contents of these, it 

 be sought to arrive at a division of a forest into equivalent 

 partitions, it will be found that constant modifications of 

 the division first made are seen to be necessary. By 

 proceeding to the work of partition with an extensive 

 knowledge of the natural history of the trees on the 

 ground, of the process of tree growth, and of much per- 

 taining to meteorology, and geognosy relating thereto, the 

 work will be found to be more easy ; but with all the 

 forest science which has as yet been secured, the work 

 must be to some extent tentative still ; and this is 

 accepted as a fact by the most advanced foresters of 

 the day. 



And while this has been accepted as a fact, it has also 

 been found that divide the forest or coppice wood as you 

 ma y> you do not secure a sustained production through 

 successive cycles of the revolution or rotation of exploita- 

 tions, The second crop is not always, or indeed often, 

 equal to the primitive or original, nor the third to the 

 second. 



It is possible ofttimes to trace in embryotic struc- 

 tures the rudiments of the organs of the fully developed 

 organism ; but how different are the appearances presented 

 by the two ! How like, and yet how unlike, are the 

 chrysalis and the butterfly! Similar is the similitude 

 and the difference between the old system a tire et aire, 

 and the system of forest economy now carried out in 

 Germany and in France, and in most countries on the 

 Continent of Europe the most advanced forest economy 

 of the day. 



There is in this system of management a three-fold 

 object sought, production soutenue^ regeneration naturelle, 

 and amelioration progressive / not one or other, but all of 

 these combined, and so combined not only that each shall 



