CONTINENTAL NOTES — FRANCE. 29 



The following table shows the diminution in volume : — 



Diameter in centimetres : 



20 I 25 I 30 I 35 I 40 I 45 I 50 I 55 I 60 I 65 l^l^^f' 



Volume in cub. metres of the average tree : 



No. 85— -390 I -680 I 1-044 j I '522 ! I "982 I 2-598 I 3-209 I 3-872 I 4-612 I 5-421 I 0-719 

 No. 87—544 I -896 I 1-286 I 1-802 I 2-427 I 3-071 I 3*791 ! 4-586 I 5-471 I 6 420 I I -240 



Comparison per cent. — No. 85 to No. 87 : 



^71-8 I 75-9 I 8i-2 I 84-5 I 817 I 84-6 I 847 I 84-4 I 84-3 I 84-4 I 57-9 



76-3 83-6 84-5 



Reduced to the hectare the countings show that : — 



No. 85 contains per hectare 275 trees of a total volume of 



197-9 cubic metres. 

 No. 87 contains per hectare 353 trees of a total volume of 



437-5 cubic metres. 

 Comparison per cent., No. 85/No. 87, 77-9 trees of 45-2 

 cubic metres. 

 Thus the bare compartment now contains 22 per cent, fewer 

 trees than the normal compartment, with only 45 per cent, 

 of its volume. 



Another example of the same kind is to be found in the 

 inspection of Valence, where the communal forests of Vassieux 

 and Marignac, alongside one another, are absolutely similarly 

 situated in all respects, except that in the former case the local 

 villagers can get at the forest, whereas the latter forest is 

 protected by cliflFs. Each forest contains about two-thirds 

 silver fir and one-third beech. 



Taking recent fellings in each forest, and considering them 

 from the point of view of the length of utilisable stem of the 

 silver fir, we have 



Diameter in centimetres 



Comparison per cent — 

 Vassieux "1 

 Marignac / 



Thus the older the silver fir grows the more the proportion 

 of utilisable bole increases in Marignac as against Vassieux — in 

 the proportion of about 3 to 2. The Working-Plan of Vassieux 

 was revised in 1908: that of Marignac in 1909. From the 



