An elastic vibrator dissipates energy through air resistance and internal friction. The vibrator also dissipatbs energy at its supporting Point. When the support condition is perfect there is no energy loss. Perfection means that supporting point does not move even when a force acts at that point. Actual supporting point does move a little when a force acts there. By assuming a linearity between force and movement at the supporting point, influence of several factors to the energy dissipation is calculated and asserted by experiments. The result tates that a frequency of an equivalent vibration system of the supporting point is the most important factor. Because of a movement of the supporting point, frequency of the vibrator is altered. Instability of supporting causes a frequency instability of the vibrator.
His Imperial Highness the Prince Takamatsu is a brother to the Present Emperor of Japan. The Prince has a collection of timepieces which is not very large, but each is very excellent as an antique. The Prince is not a positive collector and he seems to have inherited it as his ancestors' fortune. In his collection the writer found a stackfreed watch, the first discovery in Japan. Though the movement together with the dial and hand underwent reconstruction, the original watch seems to have been made in the 16th century or so. One more timepiece can be added to the existence of the oldest timepiece-the clock now kept at Kunozan Toshogu in Shizuoka City made in 1581 in Madrid and once owned by Iyeyasu Tokugawa.