PRODUCTION OF NATURAL SAND GENERATING SOUND IN WATER AND SOUND-GENERATING MATERIAL PRODUCED BY USING THE SOUND-GENERATING SAND

摘要

PURPOSE:To obtain natural sand exhibiting a sound-generation characteristic similar to that of squeaking sand when put into a vessel together with water by preliminarily washing and completely removing the soil attached to sand grains having a prescribed grain size and obtained from a clay-containing sand layer and washing the cleaned sand in a water- containing vessel while subjecting the sand together with the water to linear or circular motion. CONSTITUTION:Soil attached to natural sand having glittering characteristic and a grain size of 0.1-2mm and preferably composed mainly of quartz crystal is completely removed from the sand by preliminary washing with water. The washed natural sand and water are charged into a cylindrical vessel at a volume ratio of 1:1 and subjected to linear or circular motion principally comprising the reciprocating motion or a gyration with a definite radius while keeping the cylinder in vertical state. The sand grains are rubbed with each other in water by this process. The soil and other foreign materials attached to the surface of the grain can completely be removed and the sharp edges of the grain are rounded. The washing should be carried out without damaging the surface of the sand grain. The moving speed of sand in the washing process is preferably 10-5m/s and a sound-generating sand can be produced by washing for =60hr. Sound of high frequency can be generated by further washing the sand for about 500hr.