Hard-alloy Tools Sand-blast at www.japanese-home-gardens.com

Jet piercing for strain relief consists of feeding a flame of a combustible mixture of oxygen and fuel oil through a nozzle to the rock surface to generate a temperature over 5000°F. A stream of water joins the flame to disintegrate the rock into fragments. Wire saws are widely used for block-trimming and subdivision in fabricating mills and there has been notable progress in the use of diamond-toothed saws, hard-alloy tools sand-blast tools and sand-blast in fabrication Surfacing machines of many types are in use, as are gang saws, pneumatic tools and plug and feather wedges. Mobile cranes on tires and crawlers are coming into wider use for handling stone blocks in the quarry. See also BUILDING—Materials (Masonry) ; LIMESTONE—Uses and Distribution; MARBLE; MASONRY.

The wind takes the sand and dust from the surface of the alluvial fans, plus any sand produced by weathering, and blows it into dunes. Sand grains are not carried far in the air, but the strongest wind causes the grains to move in series of bounces [10]. Although they are never lifted more than 1m (39in) above the ground, the wind-blown particles "sand blast" any rock or pebbles in their path and polish the surface of any pebble facing the wind.

Young children's observations are frequently crude and may lead to conflicting ideas about the same item. This was illustrated by an observation of four year old children with limited vocabulary playing in the sand. When encouraged to talk about the texture of sand some said the sand was hard, some said it was soft. One said it depended on the way it was handled, if left to Filter through the fingers it felt soft, but if rubbed between the fingers it was rough. The same children found difficulty in describing the colour of sand. Some said it was brown or yellow and disagreed with the view that sand was made up of lots of different colours.