Anemometer from the straight tube is connected to the top of the sealed chamber and the pipe from the small tubes is directed into the bottom inside the float. Since the pressure difference determines the vertical position of the float this is a measure of the wind speed. The great advantage of the tube anemometer lies in the fact that the exposed part can be mounted on a high pole, and requires no oiling or attention for years; and the registering part can be placed in any convenient position. Two connecting tubes are required. It might appear at first sight as
Cylinder set measure "γ" is the standard Gaussian measure on R. The canonical Gaussian cylinder set measure on an infinite-dimensional separable Hilbert space "H" does not correspond to a true measure on "H". The proof is quite simple: the ball of radius "r" (and center 0) has measure at most equal to that of the ball of radius "r" in an "n"-dimensional Hilbert space, and this tends to 0 as "n" tends to infinity. So the ball of radius "r" has measure 0; as the Hilbert space is a countable union of such balls it also has measure 0, which is a contradiction.