Show CURIOUS FACT LITTLE KNOWN but it la easily possible for one to boll and freeze water at the same time it Is a curious tact that water may be boiled and frozen at the same time the temperature at which water boils depends simply upon the air pressure upon its surface if there be a high pressure the water must be rendered a good deal hotter in order that it may boll than would be the case at a low pressure in mountainous regions where the air pressure Is a good deal lower than at sea level water boils easily at a low temperature in cooking vege tables that require a certain degree of heat when the water boils before that degree of heat Is attained the vegetables will not get done consequently quent ly they must be placed in a closed boiler so that the generated steam will create sufficient pressure tor the water to boil at or beyond the required temperature in the experimental proof of this tact the water Is placed in a vessel and the air Is exhausted from above the surface of the w ater As the proc ess of pumping continues the water will boll violently the steam congeal ing on the sides of the exhaust vessel it the pumping Is continued for a suf period and the outside Is cooled below the freezing point the water will continue to boll and bubble until it is frozen into a snowy mass of ice the fact Is utilized in the estimation of the height of mountains ordinarily at sea level where the pressure Is about 30 inches of mercury water boils at degrees fahrenheit now it it Is noticed that at a certain place it bolls a few degrees lower the height of that place may be easily ascertained by the comparison with a table made out tor this purpose in general for every degree the boil ing takes place under a height of about feet Is counted athla prin caple does not of course apply to wa ter alone but is characteristic of all liquids |