Note 51 — Chapter II · ON MAGNITUDE
Reading edition
The fact that the limb tends to swing in pendulum-time was first observed by the brothers Weber (Mechanik der menschl. Gehwerkzeuge, Göttingen, 1836). Some later writers have criticised the statement (e.g. Fischer, Die Kinematik des Beinschwingens etc., Abh. math. phys. Kl. k. Sächs. Ges. XXV–XXVIII, 1899–1903), but for all that, with proper qualifications, it remains substantially true.