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Today's chemist can claim to have spent time learning "the secrets of the mystics," as he presents three sands of different colors. Each color can be ...
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DOUGLAS D. SMITH Guilford High School Rockford, Illinois 611 11

Magical Sand Basic Effect

Today's chemist can claim to have spent time learning "the secrets of the mystics," as he presents three sands of different colors. Each color can be made a clue to a question: green could mean a bountiful crop or yes; red could signify war, fire, or no; yellow could represent gold or riches. As an appropriate story unfolds, place a handful of each sand in a large opaque bowl. Then, to emphasize the main points of the story, bring the sands out of the water and show them to be dry and loose. In closing, the container is shown to be free of sand or hidden compartments by pouring out the water and having the container available for inspection. Enhancements

1) The container can be of clear sides and a paper or plastic opaque cylinder placed around the outside of the container. 2) By incorporating the "iodine-clock" reaction with a clear container, you would be able tomake the solution opaque and hide what happens in the bowl. By using a thiosulfate solution a t the end of the demonstration, the solution can be made clear. One method of introducing the desired chemicals would be to have the iodine solution in the bowl container and have

the other chemicals saturate a small sponge. By secretly squeezing the sponge, the solution becomes opaque. At the end, yon may clear up the solution by introducing thiosulfate from a sponge or hollow wand. Classroom use

As in other "magic," a "correct" answer or explanation is not given. The students are asked to provide methods and accurate information that may be used to provide a scientifically possible answer. Notes

1) As chemists we realize that the sand must be waterproof and stickv enoueh to stav together in the solution. At one time. animal f i t s we;e bakedwich the sand to produce the waterproofing, but these would become rancid and not always stick together. One other method is to incorporate wax around the sand. I do not know what methods are currently used. 2) The effect should be available in a magic shop. It comes with various titles; two of them are "The Sands of Time" and the "Sands of Egypt" and costs around twenty dollars. 3) With the added "Iodine-clock reaction" and adequate practice, you have a memorable demonstration for open house or a great routine for a school talent show.

Incarceration is not all pain and worry, as I discovered during a recent thirty (30) day sentence. I also had.the opportunity to pick up some interesting material for the classroom.

for the New Yorker magazine and collected them into a book. The title storv is an e x a m ~ l eof how a doctor traces the unusual deaths of eleven men to the acridentul substitution of a common chemical for sodium chloride. 'The book contains examples which could fit into a class presentation, could be assimed for extra credit reading, - or could be quoted to impress family physician.

Sodiom Chloride

Gallium Usage

Eleven Blue Men and Other Narratives of Medical Detection" is a book recommended by a highly skilled infectious disease investigator. Berton Roueche wrote a series of articles

Radioactive gallium citrate (Ga 67) is used to detect the locations of infections in the body. The use is based on the observation that gallium citrate concentrates in the areas

Ideas from a Hospital Visit

Volume 57, Number 5. May 1980 1 363

where white blood cells are also concentrated, which in my case, were the sites of infection. The patient receives an injection of the gallium solution, and after 24,48, and 72 hr he is used to expose an X-ray film. From a patient's view, the experience is disconcerting as you lie motionless on a table for about 25 min and radiate. The disadvantages of the radiation are offset by the docton

knowing the location and severity of the infection and the patient not needing an exploratory examination via surB '-". -e -,