Page:Popular Science Monthly Volume 90.djvu/241

 Snow: A Curse and a Blessing

The same blanket of snow in high mountains that sends destruc- tive avalanches down into the valleys will serve to feed irri- gation streams in the spring and make agriculture possible

���The hc_. . — ■- _:iowfall in the whole country, as far as known, occurs in the high Sierra Nevada, of Cahfomia, where the houses are often buried up to their eaves. This snow, melting, furnishes most of the water for irrigation in the California lowlands

��IF snow were only a thing for children to romp in and poets to prate about, the United States Government would prob- ably not be minded to publish throughout each winter a weekly snow bulletin, com- prising telegraphic reports from all parts of the countr\', nor would it send out its experts to probe and map the mountain snowfields for the purpose of determin- ing' the probable water-supply from this source.

A good snowfall chart of the United States will show you that, in a normal winter, the total amount of snow falling in various parts of thecountn,^ ranges from nil in southern Florida and parts of California to more than one hundred inches in northern Maine and on the southern shores of Lake Superior, and to three hundred or four hundred inches in portions of the Rocky Mountains and the Sierra Nevada.

The occasional heavy fall of snow pre- sents a problem to the street-cleaning authorities in our great cities that is not yet fully solved. Only a few years ago the uniform method of dealing with this prob-

��lem was to wait until the storm was over and business effectually tied up; then press into service as many men and wagons as possible, and gradually dig the city out.

The tendency now is to begin work as soon as the snow has covered the pavements if the indications point to a continuance of the storm. A most important advance consists in a recognition of the extent to which the sewers can be utilized in snow removal. While some authorities advocate flushing the snow into sewers with a hose, the method which has recently proved suc- cessful in New York City is to collect it in wagons and dump it into the manholes, under proper supervision to prevent an unnecessary amount of solid matter from being dumped along with it. Two cubic yards a minute can be shoveled into a twenty-four-inch manhole, and, under ordi- nary conditions, it is found that the entire amount is melted within three hundred feet of the manhole by the relatively warm water in the sewer. The cost is a small fraction of that entailed by the old method of hauling to riverside dumps.

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