Least relative humidity is found in places southwest of Arizona, where
the average is about 40°. Fifty degrees humidity means half as much
moisture as is necessary for complete saturation. The average in other
parts of the country is from 60° to 80°.
Steel boils at 3500°; water boils at 212°; liquid air submitted to a
degree of cold where it ceases to be a gas and becomes a solid is 312°
below zero. Professor John Dewar of England is credited with some of the
most remarkable experiments with low temperature, and at these
temperatures made some wonderful discoveries. He went down so cold that
he could freeze liquid air back into a solid; he continued further until
he reduced hydrogen, a very light gas, to a liquid. This was at 440°
below zero. One of the most remarkable things he did was to freeze
hydrogen into a solid.
Water boils at 183.2° Fahrenheit on top of Mt. Blanc; water boils at
194° Fahrenheit on top of Mt. Quito.