82 SECTIONAL ADDRESSES 
Douglas has also proved rainfall records at Flagstaff, Arizona, at eleven 
year periods for 600 years, and this checks up with the known solar record. 
Though we cannot entertain extravagant hopes that this mode of 
research will help geologists, we may learn something of periodic occur- 
rences in the past. It is true that at present single trees are little use, but 
methods may yet be found for using the records of such single trees. 
The largest fossil tree I know, and I think it is the largest yet discovered, 
is a stump said to be of the Sequoza type and of Miocene age at Henderson’s 
Ranch, near Florissant, Colorado. It is 17} ft. in diameter, and 1o ft. 
high, quite comparable in girth, therefore, with the Big Trees of to-day. 
A record of its rings should be made, as also of those of at least a dozen 
other stumps in that area. Then again the ‘ petrified forests’ of Arizona, 
Egypt, Burma, and elsewhere should also be recorded. The game 
might not be worth the candle, but it might add yet another minor link 
to the chain of ideas with which fossil plants have affected the philosophy 
of geology. 
