Note 748 — Chapter XIII · (continued 2)
Reading edition
“What forces were in operation to cause this oscillation of the newspaper?” asks J. W. Phelps, who quotes the case—“These were the rapid upward motion of heated air, the downward motion of cold air, the translatory motion of the surface breeze, and the circular motion of the whirlwind. But how could these combine so as to produce the oscillation?” (Lecture on “Force Electrically Explained.”)