Saturday, February 23, 2008

Making Ice Water From the Sunshine


EL PASO, Tex. — Manufacturing a drink of ice water with nothing cooler than the sun's rays and dry tropical air would probably seem under the province of the magician to the easterner. It is nevertheless a fact that from these ever-available agencies the greater part of the population of Texas, Arizona and New Mexico manufacture their own ice water. This not only serves for drinking purposes, but also provides an efficient medium for the ordinary requirements of refrigeration — for in the cruder sections of the great southwest the artificial production of ice is still a trifle too costly to be feasible.

The secret lies wholly in the construction of the little red receptacle in which the water is placed. This is a simple Mexican creation, and in that language is called an olla, the two l's being silent according to the Spanish pronunciation of the word. In northern Mexico olla making is a very profitable industry to the inhabitants, who carry them over into Arizona on the backs of burros.

The olla is made from a crude clayish mortar. In drying the composition becomes very porous, and it is this essential characteristic which contains the secret of the cooling process.

It is filled with water and hung up, preferably in some place which is exposed to the wind if there be any. The moisture seeps through the porous composition. The process is very slow, and the moisture which exudes evaporates into the receptive, dry atmosphere in such equable proportion that scarcely more than a drop a minute trickles away from the bottom of the olla.

It is this continuous and fairly rapid evaporation which produces the cold. Immediately the sides of the olla become chilled, and the water within grows gradually cooler. In less than an hour from the time the phenomena is begun the water is cold enough for drinking purposes, no matter how warm it might have been when poured into the receptacle. Two or three hours later it is cold enough to fill the ordinary requirements of refrigeration for bottled milk, butter and other culinary necessities.

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