244 PHYSIOLOGICAL BOTANY. PART II. 



Where a complete section cannot be obtained, a la- 

 teral incision may be made, and by counting the number 

 of rings in the portion exposed, an approximation may 

 be made to the whole number ; care being taken to make 

 allowance for the more rapid increase of the trunk in 

 the early stages of its growth. 



In other cases, some judgment may be formed of the 

 ages of very old trees, by ascertaining the rate at which 

 others of the same species have increased within known 

 intervals of time, and by then applying the rule thus 

 obtained to the tree in question. The observer must 

 be cautious when he is examining very large trees, lest 

 he should be deceived by several trunks having become 

 blended into one. 



('21 1.) Examples of Longevity in Trees. As ex- 

 amples of the mode in which approximations have been 

 made towards the ages of very old trees, we may men- 

 tion certain individuals of the lime, yew, and baobab. 



1 . The Lime. A tree of this description was 

 planted at Fribourg in Switzerland, on the day when 

 the news of the victory of Moral arrived, in 1476. 

 In 1831, this tree was 13 feet [) inches in circum- 

 ference, which gives l lines in diameter per annum 

 as the mean rate of its increase. But as this tree 

 is confined in a town, we may allow 2 lines per an- 

 num as the rate of increase for other trees more freely 

 exposed, whose ages we may wish to ascertain. Now, 

 there is a lime near Neustadt on the Kocher, in the 

 kingdom of Wurtemberg, which was of large dimen- 

 sions in the year 1229 ', since it is stated in ancient 

 records, that the city was rebuilt after its destruction 

 in that year, " near the great tree." A poem, bearing the 

 date of 1408, describes this tree as having its branches 

 at that time supported by (>7 columns. Evelyn, in 

 l6'6'4, mentions the number of columns then to have 

 been 82 ; and in 1831 they had increased to 106'. 

 At this period, the trunk was 37 feet 6' inches and 

 .'> lines (\Vurtemberg measure) in circumference, be- 

 tween 5 and 6 feet from the ground. This, upon an 



