On the Longevity of ike Yew. 33 



of 150 and 250 years, rather than pass at once from t,he 

 vigorous growth of youth to the slower progress of more ad- 

 vanced periods. I have had no opportunity to obtain satis- 

 factory evidence on this point, though sections from the north 

 and south sides of a yew at least 250 years old, but whose 

 diameter could not be fixed, owing to great inequalities and 

 excrescences, showed an increase of 2 in. diameter in 21 J 

 years, or rather more than one line annually. De Candolle 

 says that, between 150 and 250 years old, the yew grows 

 rather less than one line annually. I will therefore take the 

 mean, and allow 100 lines, or, to avoid fractions, 96 lines, or 

 8 in. for its growth between 150 and 246 years, only employing 

 the reduced rate obtained from actual sections for its subse- 

 quent periods. Then, at 150 years old, its diameter would 

 be 25 in., or 300 lines ; and at 216 years, 33 in., or 396 lines; 

 and, deducting this from its present diameter of 8 ft. 6 in., the 

 subsequent increase will have been 5 ft. 9 in. Now, a diameter 

 of 5 ft. 9 in., at 34 rings for each inch of the radius, will contain 

 1173 rings or years' growth ; to which add 246, its assumed 

 age when 2 ft. 9 in. diameter, and we find its present age, by 

 the nearest approximation at which we can arrive, to be 1419 

 years. I have not made any deduction for the bark, because 

 in the yew it is too thin sensibly to affect the general result. 



The other aged yew which I have examined is of still 

 greater dimensions than the last, and is growing in the church- 

 yard of Darley in the Dale, Derbyshire. This is a female, 

 with a solid trunk, forking, at 7 ft. above the ground, into two 

 nearly upright boughs, which reach a height of about 55 ft. ; 

 but its head has not the breadth or luxuriance of the Gresford 

 yew. Its circumference at the base is 27 ft. ; at 2 ft. 4 in. 

 above the ground, 27 ft. 7 in. ; at 4 ft., 3 1 ft. 8 in. ; and at 6 ft., 

 30 ft. 7 in. At 4 ft. high, there are excrescences which swell 

 the trunk beyond its natural size ; I would therefore omit that 

 measurement, and take the mean of the three others, which 

 will be, circumference 28 ft. 4 in., diameter 9 ft. 5 in., disre- 

 garding fractional parts. Its mean diameter is therefore 1 356 

 lines, which, according to De Candolle's method, would also 

 be the number of its years. 



Let us now endeavour to find its age by the number and 

 thickness of its annual rings. 



A horizontal section on the north side contained, in different 

 parts of its surface respectively, 57 rings in 1 in. ; 71 rings in 

 2 in.; 62 rings in 1 in.; 66 rings in 1 in. ; giving an average 

 number of 51 rings per inch. A similar section, from the south 

 side, contained 53 rings in 1 in. ; 68 rings in 2 in. ; 67 rings 

 in 2 in. ; 66 rings in 2 in. ; and 39 rings in 1 in.; giving an 



Vol. I. — No. 1. n. s. d 



