A pendulum is a weight suspended from a pivot so that it can swing freely. When a pendulum is displaced sideways from its resting equilibrium position, it is subject The Early History of Seismometry (to 1900) by James Dewey and Perry Byerly The Development of the Seismograph in Japan Cecchi’s seismograph notwithstanding Pendulum toys have been made in Seiffen, Germany since the early 1900s. They can be put on a bookshelf, mantle, window, table, etc. When the pendulum is moved the toy A pendulum clock is a clock that uses a pendulum, a swinging weight, as its timekeeping element. The advantage of a pendulum for timekeeping is that it is a harmonic The Early History of Seismometry (to 1900) by James Dewey and Perry Byerly The Earliest Seismoscope The Chinese philosopher Chang Hêng [Chang Hêng is Antique and collectible American mantel clocks are an investment in time. Antique mantle clocks can beautify your home.I created this video with the YouTube Video Editor (http://www.youtube.com/editor)Early Electric Motors . The Development of the Electric Motor. As is so often the case with invention, the credit for development of the electric motor belongs An animation of a pendulum showing the velocity and acceleration vectors (v and a). Image: WikipediaShop for rare and collectable antiques in the UK on Gumtree. Browse vintage items like rocking horses, antique dolls, pocket watches tea sets and much more.