Read it through once

"Upon connecting the telephone between two nails driven in any growing tree along the route of the line, and at a reasonable distance therefrom, the telephone responded to this note with great clearness, and when the distance was not more than 100 feet, the sound was very loud. For this experiment no microphone need be used, nor any source of electromotive force other than that induced in the tree itself, the telephone being connected directly between two nails driven into the tree....