Note 61 — Chapter XIV

It was often of great importance to me to ascertain these apparent slopes with some degree of correctness. In order to do so without the trouble of carrying any instrument (except my compass and spirit-level), I had my Alpine pole made as even as a round rule for about a foot in the middle of its length. Taking the bearing of the mountain, placing the pole at right angles to the bearing, and adjusting it by the spirit-level, I brought the edge of a piece of finely cut pasteboard parallel, in a vertical plane (plumbed), with the apparent slope of the hillside. A pencil line drawn by the pole then gave me a horizon, with which the angle could be easily measured at home. The measurements thus obtained are given under the figures.