Author : Terrestrial Electric Observatory
Publisher : Forgotten Books
ISBN 13 : 9780266817024
Total Pages : 26 pages
Book Rating : 4.8/5 (17 download)
Book Synopsis Bulletin of Terrestrial Electric Observatory of Fernando Sanford, Palo Alto, California, Vol. 4 by : Terrestrial Electric Observatory
Download or read book Bulletin of Terrestrial Electric Observatory of Fernando Sanford, Palo Alto, California, Vol. 4 written by Terrestrial Electric Observatory and published by Forgotten Books. This book was released on 2017-10-27 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from Bulletin of Terrestrial Electric Observatory of Fernando Sanford, Palo Alto, California, Vol. 4: March 1927 General outline of work for the yam - During the year 1926 observa tions on the diurnal variation of earth potential and air potential were carried on at this observatory. On account of the serious disturbances due to ground currents from trolley lines, the work of previous years on earth-current variations was discontinued. No records were made during the month of May. No air-potential records were made in February, and no earth-potential records in April. During the year the variation in earth potential was recorded on 244 days and air-potential records were obtained for 225 days. The method of making these records has been described in previous numbers of this Bulletin. Briefly, two quadrant electrometers were used. Both stood on the same wooden pier inside a cage of wire netting which was four feet square at its base and eight feet high. The electrometer used for measuring variations of earth potential had one pair of quadrants earthed through the case of the instrument, the wire cage, and the water system of Palo Alto. The other pair of quadrants was connected by an insulated wire to an insulated metal conductor which was inside a thermos bottle, a metal case, and a porcelain jar. The variation in potential differ ence between the two pairs of quadrants has been attributed to a variation in the electrical potential of the ground at this place. Reasons why this change has been attributed to the earth rather than to the insulated con ductor have been given in previous volumes, especially in Volume II. The air-potential electrometer had its two pairs of quadrants connected to two copper balls, one seven inches and the other eight inches in diameter, which were suspended above the roof of the observatory. One of these balls was three meters above the other, which was only one meter above the roof. Both balls were enameled to insure high insulation, and both were suspended by flint glass insulators inside of bottles from which the bottoms had been removed. This was to Shield them from rain and dust. The wires leading to the electrometer were heavy, rubber-insulated wires which were also shellacked. It seems improbable that the balls or con ducting wires could have taken rapidly changing charges from the air. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
