Helium is non-inflammable and lessens the risk of airship operation. But it costs $100 per 1,000 cubic feet andin spite of the goldbeater's skin covering the cotton bagsit leaks out to the tune of several hundred dollars a day. The British Air Secretary now announces a different scheme, whereby cheap hydrogen will be surrounded with a shell of inert gas, minimizing fire risk at a tenth of the cost of helium.
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