Nov. 1892.] BOTANICAL SOCIETY OF EDINBURGH. 



479 



ground. Original measurement by Sir E. Christison ; sub- 

 sequent ones by me. Given in feet, inches, and tenths of 

 an inch. 



3. Estimation of Age in Ancient Beeches. 



The data yield a greater range than in the oaks. In 

 Mr. Hutchison's cases we do not know whether the 

 measurements were taken at a marked line. On the 

 whole, however, the figures are confirmed by the results 

 in the other tables. 



Estimation of Age of the Navbattle Beech. — Taking the 

 ascertained rate of 0'40 inch for the last 14 years, at a 

 girth of 19 feet, and supposing, according to De Candolle's 

 theory, that the rate had always been nearly the same 

 except in early youth, we get about 550 for the age; 

 but how fallacious this would be is actually proved by 

 measurements taken above a century ago, as will presently 

 appear. Eeverting, therefore, to the mode of estimation 

 already explained, let us first take the data which show 

 the most rapid growth. These we find in the large beech 

 at Craigiehall (1 /). fortunately for us, though unluckily 

 for the tree, a violent storm tore away one of the large 

 limbs, producing a gap 4 feet wide in the 9 feet long- 

 stem, right down to the pith. In 1879 Sir E. Christison 

 describes the tree as 70 feet high, luxuriant in foliage, 

 with branches extending 50 feet from the trunk to north, 

 soutli, and west, and only deficient to the east on account 

 of the gap. In this gap he was able to count the rings, 

 at a height of about Gi feet, throughout the whole radius 

 of 32^ inches, except the inner five, which were decayed, 

 and six more, beginning at a foot from the centre, in which 

 the rings were too indistinct to be counted. It is easy to 

 make allowance for these, however, and dividing the radius, 

 in the diagram drawn up by Sir Eobert, into spaces of 



