366 
POPULAR SCIENCE REVIEW. 
its exact vegetative condition in a moment before bis eyes, at 
any one of tbe previous years of its past bfe. 
Tbe twig represented by our plate was cut from one of tbe 
lower branches of an old beech, in Epping Forest, on tbe 7th 
of March, 1863. As there are thirteen sets of annuli on its 
main or central stem, it has evidently stopped growing thirteen 
times, and borne thirteen generations of winter leaves, and as 
many generations of summer leaves ; consequently it is thirteen 
years old, and it must have commenced growing from the bud 
in the spring of 1850. It is also plain, that the first and second 
side-shoots remained in the bud condition throughout the whole 
of the year 1850, and made their first growth from the bud in 
the spring of 1851. Hence, only twelve sets of annuli can be 
counted on these two shoots and the same law is apparent 
throughout the entire series of shoots, which are fifteen in 
number ; each is one year younger, and will be found to have one 
set of annuli less than its parent stem. Thus the fifth branch 
above, the set of annuli marked 53, is numbered 9, because 
there are on its surface the marks left by nine generations of 
winter leaves, or nine sets of annuli ; it is therefore nine years 
old, or one year younger than its parent axis, which numbers 
ten sets of annuli, counting from annuli marked 53 upwards, to 
1862. Similar observations apply to shoots numbered 8, 6, 
and 4. 
We must, however, except shoot 11 numbered 3, and shoot 
10 numbered 2. These shoots were formed from buds which 
were matured in the autumn of 1857 and 1856, or five and six 
years ago. This is proved by the leaf-scar at the base of the 
shoot. Yet there are only three sets of annuli on one, and 
two sets of annuli on the other ; consequently the former shoot 
must have been torpid for fiwo, the latter for four years. 
Another feature which presents itself for consideration, is the 
variation in the amount of stem between the sets of annuli. 
This shows that the growth varies from year to year, and that 
powerful growths are sometimes followed by growths greatly 
retarded. All twigs over whose surface the progress of yearly 
growths may be traced for a series of years, show more or less 
these marked differences of growth. Each branch has, in fact, 
its own peculiar history of growth, and trees differ not more 
widely in this respect than two branches on the same tree. In 
the consideration of a tree, we have to deal not with a product 
of crystallization such as the lead tree, or the dendritic forma- 
tions on a frozen window, but with matter living and organized. 
The tree is therefore no stiff, unyielding form, but an easily im- 
pressible body, whose growth fluctuates with the favourable and 
unfavourable state of the weather from year to year. 
The distance between two sets of annuli, estimated from the 
