ffected by atmospheric conditions, brushes of each pair are connected by a narrow strip During the winter and early spring they are pro- and may be relied on in all weathers for results of some of tin foil attached to the glass. The stationary glass tected by a series of brown scales, inside which… … shaft is provided with a grooved pul- folds, the number being determined ley. A solid shaft placed within the by the number of ribs or veins. For tubular shaft, and projecting beyond such folds, however, there would be the ends thereof, carries upon one end a glass disk, ana the brushes at the…
Internet Archive · Public domain (published before 1931). Free to use for anything.
