CHAP. IV. FUNCTION OP NUTRITION. 245 



estimate of 2 lines per annum for its growth, would 

 make it to be between 700 and 800 years old. But as 

 it is certain that it has not increased for some centuries 

 at so rapid a rate, it may fairly be considered as above 

 1000 years old. 



2. The Yew. M. De Candolle ascertained, by in- 

 specting three yews which had been felled, that they 

 had grown at the rate of 1 line in diameter per annum 

 during 150 years; and that one of them had in- 

 creased somewhat less rapidly during the succeeding 

 century. The rate thus obtained, he applies to the 

 growth of some English and Scotch yews, whose di- 

 mensions were given by Evelyn in 1666, and Pennant 

 in 1770. Among these, is a yew which the former 

 describes as growing in the churchyard of Braburn in 

 Kent, which was 58 feet 9 inches in circumference, or 

 2820 lines in diameter ; indicating by the above rule, as 

 many years for its age. If now living, this tree, according 

 to such an estimate, would be more than 3000 years old. 

 It may be doubted from the following account, whether 

 the rate at which the yew increases in England is not 

 more rapid than in France. There are two fine healthy 

 trees of this kind in the churchyard at Basildon in 

 Berkshire, which, according to the parish register, were 

 planted in 17^6. In 1834 they were very nearly of the 

 same dimensions, and the largest measured 9 feet 3 inches 

 in circumference at 4 feet from the ground : this gives 

 444 lines for its diameter, or 4 lines per annum as the 

 mean rate of increase for a century. It appears how- 

 ever by some other entries in the same register, that 

 the tree had grown more rapidly during the former 

 half of this period than it has done latterly. Taking 

 these data as a guide for estimating the ages of some 

 old yew trees in the churchyards of two neighbouring 

 parishes, it would seem that De Candolle's calculations 

 should be reduced by about one third, in order to ob- 

 tain a more correct approximation than that which he 

 has given for trees of this description. It was found, 

 B 3 



