and into the cloud below.
On the ground, Dr. Langmuir watched excitedly and saw snow falling from the bottom of the cloud. When Schaefer returned to the ground, blue with cold, Langmuir ran to him, shouting, You have made history! And indeed he had. Almost as soon as the news of his accomplishment was sent across the United States and around the world, a hundred other rainmakers were throwing dry ice into clouds or seeding the clouds as it was called.
When Schaefer discovered that ice crystals could be formed without finding the right material to make centers for the crystals, he stopped searching for such materials. But another young worker at General Electric, Bernard Vonnegut began looking through a chemistry book for some chemical compound that might have the right size and shape to form crystals around it. He found what he was booking for. It was a compound called silver iodide. He got some silver iodide and developed a way of burning it to produce tiny particles that would separate in the air and form snow he hoped.
Finally he shot the material up into the air and waited for the storm. Nothing happened. He couldnt understand why. The compound ought to form enters for crystals. He asked a scientist to examine the chemicals he had used. There was the trouble. The silver iodide he had used was not pure.
He got more of the material, performed his experiment again, and there were the snow crystals! Today, scientific rainmakers generally use silver iodide, Which can be sent into the air from the ground by means of a simple, inexpensive machine. This process is more satisfactory than the use of dry ice which can be destructive.
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