Anemometer Lind was not the first it was the most practical and best known anemometer of this type. If the wind blows into the mouth of a tube it causes an increase of pressure on one side of the manometer. The wind over the open end of a vertical tube causes little change in pressure on the other side of the manometer. The resulting elevation difference in the two legs of the U tube is an indication of the wind speed. However, an accurate measurement requires that the wind speed be directly into the open end of the tube; small departures
Convergence in measure formula_14, "μ" be Lebesgue measure, and "f" the constant function with value zero. (The first five terms of which are formula_19) converges to "0" globally in measure; but for no "x" does "f(x)" converge to zero. Hence "(f)" fails to converge to "f" almost everywhere. There is a topology, called the topology of (local) convergence in measure, on the collection of measurable functions from "X" such that local convergence in measure corresponds to convergence on that topology. This topology is defined by the family of pseudometrics where In general, one may restrict oneself to some subfamily of sets "F" (instead