Page:Popular Science Monthly Volume 89.djvu/880

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Taking the Temperature of a Dam

Forty-seven thermometers are buried in the concrete of the Kensico dam

Bv Herbert Francis Sherwood

���The thermometers arc buried at predetermined levels and points in the dam and are connected by buried cables with switchboards at central points

��OSE fliiy, a year a^o, I paid my first visit to the ^ri-at Kensico dam, tliree miles north of White Plains, X. V.. <()untcd atnoiiK the notable dams of the world. It is intended to form a storage reser\oir in the C'.itskill system of water supply which New ^'ork city is constructing at .111 expenditure of Si 77.ikh),(x#o. The i.ike of Citskill w.iter behind it will he .ipprnxim.iieK' four and .i h.ilf miles in lfn^;lh. 1 1 will ha\'e .» m.iximum de|)th of one hnndred and liflylue feet, and contain upw.niU (if lliirt\ liillion e.dlotis of w.ilcr.

��It was a hliak da\ . The thermometer early in the mornini; hail registered zero. .•\ searchini; northwest wind swept down throngh the whole length of the l)asin in the Bronx valley and chilled to the ni.irrow those who went out upon the crest of the dam. .^ccompanie(l!)>• the division engineer, I descended from this exjiosed pi. ice to the long corridor extending for more than a third of a mile through the This corridor opi'ii to the sk\- at iiitcr\.ils .111(1 I astonislu'd at the w.irmth of the air encountered there.


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