![]() ![]() The substance that put the ‘time’ into night-time was discovered by Marie and Pierre Curie in 1898. In 1680 Daniel Quare created repeating watches that could tell time in the dark to the nearest quarter of an hour, but it would be a further 70 years before time to the nearest minute would be possible and even then, these marvels of miniaturisation were only available to the privileged rich. Before widespread public and domestic lighting, dark meant dark and passing hours might be marked by a chiming clock if you were rich enough, or close enough to a church. This means that early watches, however finely made or accurate, were at best part-time timepieces. Part 2: LumeĪ watch is only as good as its ability to tell you the time. Published by Elsevier Inc.Delve into the history of dial design and the elements that make up some of the most famous watch faces of our time. No clear cut, uniform mechanism for the handling of radioactive materials which turn up outside of the usual institutional sources, is currently in place.Ĭopyright © 2019. Any significant amount of radium is extraordinarily difficult and expensive to dispose of and there are only limited sites which will accept these materials. They then should either be stored in some area where the environment is protected from the radioactivity or if a very small amount of radium is present, they may be disposed of through one of several commercial sources. All objects discovered claiming to contain radium should be taken seriously and should be properly surveyed. The radium which was produced in the early part of the century is still around in various forms and is extremely difficult to dispose of. With the shift in public attitudes towards radioactivity, and increasing problems in disposal of radioactive materials, the disposal of radium presents a particularly perplexing problem. The "Buck Rogers Mystery Ring" of the 1950s was activated with polonium. However, even as late as the 1950s, there were still some items produced containing radioactivity which today would be unthinkable. Since the late 20s and early 30s the public's attitude towards radiation has shifted 180° and it is now considered an extremely dangerous and harmful material. A number of objects were produced in order to trap the emanations of radium in water for persons to drink in order to benefit from their healing effects. The wide availability of radium is a result of the public's great fascination with radioactivity during the early part of this century and a belief in its curative properties. ![]() In addition to the large amount of radium produced for scientific and consumer utilization, there were a number of materials produced which were claimed to contain radium but in fact did not, further adding to the confusion in this area. Some of these watches contained as much as 4.5 μCi of radium, and between 19 about 70 gm was produced for the manufacture of luminous compounds. In addition, the consumer market utilized a large amount of radium in the production of wrist watches, pocket watches, and clocks with luminous dials. These instruments include compasses, azimuth indicators, and virtually any object which might require some form of calibration. In addition to medical sources, a large variety of scientific instruments utilize radium in luminous dials. These objects include radium in devices which were used by legitimate medical practitioners for legitimate medical purposes such as therapy, as well as a wide variety of "quack cures." These devices may contain anywhere from a few nanocuries to as much as several hundred microcuries of radium. Antique objects containing significant amounts of radium turn up at flea markets, antique shows, and antique dealers, in a variety of locations. Radium has been distributed in a wide variety of devices during the early part of this century. ![]()
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