CHAPTER XI. 



ON THE FELLING OF OAK IN SPRING AND WINTER. 



THE bark of the Oak tree contains a substance called 

 tannin, which is of considerable value, and is used in the 

 preparation of leather. Therefore, in order to secure 

 this tannin in its 'greatest quantity, it is the practice to 

 fell, or cut down, the trees in the spring of the year, 

 when the sap is rising. Under other circumstances, the 

 trees would have been cut in the winter, while the sap 

 was down and in a quiescent state a period which has 

 been almost universally recognised as the best for felling, 

 as it is considered to ensure a better quality, and to be 

 conducive to the greater durability of the timber. The 

 value of the bark, however, generally overrides this 

 consideration, since, although the weight in proportion 

 to the contents of the timber will vary according to 

 circumstances of growth, it is always thought profitable 

 to save it, and, viewed under the commercial aspect, 

 it is not likely to be disregarded. 



The quantity of tannin contained in the bark of the 

 Oak, as ascertained by Sir Humphry Davy, varies as 

 follows, viz. : In Coppice Oak it is 32 ; middle sized, 29 

 and Oak cut in the autumn, 2 1 per cent. 



The timber and bark merchants variously estimate 

 the quantity of bark to the contents of the timber ; and 

 no doubt there is a very considerable difference in the 



