Page:Life in Motion.djvu/99

Rh the movements of the fork, and then Mr. Heath will place it in the lantern. Then you see the words, and you will observe that the letters show little curves, each of which represents about one-two-hundred-and-fortieth of a second. By counting the little curves in any letter you can measure the time I occupied in writing it.

But let us return to the question of whether ordinary voluntary contractions are twitches or tetanic spasms. Another strong bit of evidence in favour of the occurrence of what we call