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Show few poopte, .probably, know'ir tat tfc Is that enables flies to walk on' the celling. cell-ing. It has "been supposed that their ability to do to wa aQ4 to tha faetthat: each, of their . feet is a . miniature air-i pump.. This theory ,waa found to be un- sound, and It was then explained that: the feat was made possible by snaans of a viscous substance which exuded from the hairs on; thalr feet. ;'Thli' theory also was abandoned for the facts; and' the preferred, explanation, la that flies: are enabled to walk' upside , down on smooth substances by the help of capillary ca-pillary adhesion. At Investigator has found by a series of aloe calculations-such calculations-such as the weighing and measuring of hairs that a fly would be upheld by, capillary attraction were It four-nlntha as heavy again as It is. Each fly Is supposed to b furnished with from 10.-000 10.-000 to 12,000 mlnuta foot-hairs these exude an oily fluid, and it Is because of . the repulsion between a watery surface and this oily liquid that a, fly finds It difficult to mount a dampened glass.-. Harper's Weekly. - ,-,r... |