Thoreau writes in his journal:
On the left hand, just this side the centre of Wayland, I measure the largest, or northernmost, of two large elms standing in front of an old house. At four feet from the ground, where, looking from one side, is the smallest place between the ground and the branches, it is seventeen feet in circumference . . .
A[ustin]. Bacon showed me a drawing apparatus which he said he invented, very simply and convenient, also microscopes and many glasses for them which he made . . .