W. H. Samelius, Chairman
Science of Horology and Technical Board
At Mundelein College, Illinois, there has been installed in an unused elevator shaft, a pendulum that is 120 feet long with a 30 pound ball at the bottom. It takes the pendulum six seconds to make each vibration of 68 inches. The lower end of the pendulum swings directly over a dial which is charted for 24 hours of the day.
The pendulum when once set in motion, will continue to swing (or several hours in one direct back and forth movement and as the earth turns the elevator and dial, the pendulum maintains a regular course, thus showing the rotation of the earth. The pendulum is a modification of a Focault pendulum with a Longen suspension. This experiment will also aid in the study of the pull of gravity in this region.
To securely set a roller jewel, it is advisable when the shellac is thoroughly melted and before the jewel is adjusted to its final position, to move it up and down in the hole two or three times so the shellac may be carried throughout the full length of the hole, then the final uprighting and setting of the jewel may be done and when the shellac is cooled off, any excess shellac may be scraped off, using a scraper made of brass or nickel.
Our largest watch factory has automatic wheel-cutting machines, each equipped with a microscopic device for inspection purposes.
That the width of gear teeth in our small watches is .004 inches wide.
Up to approximately 1865 grandfather clocks were known as long case clocks.
Hardening copper has been considered a lost art. Today we have copper so hard it can actually be used to forge steel. It is much harder than that produced by the ancients and is today used for many commercial purposes. This copper is made by using beryllium as an alloy.
Napolean carried a watch that was wound by the motion of the body while walking. The watch was made to order by Breguet, the famous French watchmaker.
Miconcave glasses are suitable for the average open face watches. Genevas for hunting case watches. Lentille Chevees for extra thin open face cases. Lentilles for thin cases similar to Lentille Chevees but lower at the edge.
A lamp clock with a clear reservoir of oil graduated to mark the time of day as the oil is consumed was used by Philip II of Spain.
Repeating watches made for deaf people had a small opening in the case center where the hammer would project far enough through the case to strike on a finger held over the opening and by this means a deaf person would be able to tell the time at night.
Repeater watches were popular during the era when matches were scarce and when candle light was used.
The minute hand on a 16s watch travels .00026 inch with each vibration of the balance.