28 On the Building Materials of the United States. 



feet in circumference, and the largest which I had an oppor- 

 tunity of actually measuring was a Button- wood tree {Platanus 

 occidentalism on the banks of Lake Erie, which I found to be 

 twenty-one feet in circumference. I saw many trees, how- 

 ever, in travelling through the American forests, which evi- 

 dently far exceeded that size, and which my situation, as a 

 passenger in a public conveyance, prevented me from mea- 

 suring. 



M. Michaux, who has written on the forest trees of America, 

 in speaking of their great size, states, that on a small island in 

 the Ohio, fifteen miles above the river Muskingum, there was 

 a button-wood tree, which, at five feet from the ground, 

 measured 40 feet 4 inches in circumference. He mentions 

 having met with a tree of the same species on the right bank 

 of the Ohio, thirty-six miles above Marietta, whose base 

 was swollen in an extraordinary manner ; at four feet from 

 the ground it measured 47 feet in circumference, giving a 

 diameter of no less than 15 feet 8 inches ; and another 

 of nearly as great dimensions is mentioned by him as ex- 

 isting in Genessee ; but these trees had perhaps been swollen 

 to this enormous size from the effects of some disease. He 

 also measured two trunks of white or Weymouth pine, on 

 the river Kennebec, in a healthy state, one of which was 

 154 feet long, and 54 inches in diameter, and the other was 

 142 feet long, and 44 inches in diameter, at three feet from 

 the gi'ound. M. Michaux also measured a white pine which 

 was 6 feet in diameter, and had reached probably the greatest 

 height attained by the species, its top being 180 feet from the 

 ground. It is difficult for an inhabitant of our island, with- 

 out having seen the American forests, to credit the statements 

 which have been made by various authors, as to the existence 

 of these gigantic trees of 180 feet in height (being about 40 

 feet higher than Melville's monument in St Andrew Square, 

 in Edinburgh) ; but such trees undoubtedly do exist. Mr 

 James Macnab of the Royal Botanic Garden, in a paper on 

 the local distribution of different species of trees in the native 

 forests of America,* mentions having measured numerous 

 specimens of the Tinus strobus in Canada, which averaged 



** Agrituliural Journal for 183wi 



