Moulton, Forest Ray, 1872-1952 · New York, The Macmillan company · leaf 75
ficulty in deter-mining the density of the earth is due to the fact that theattractions of masses of moderate dimensions are so feeblethat they almost escape detection with the most sensitiveapparatus. The problem from an experimental point ofview reduces to that of devising a means of measuring… … Fig. 14. — The torsion balance. the point 0 by a quartz fiber OA. If the apparatus is leftfor a considerable time in a sealed case so that it is not dis-turbed by air currents, it comes to rest. Suppose the ballsbb are at rest and that the large balls BB are carefullybrought near them on opposite…
Astronomy
Internet Archive · Cornell University Library · Public Domain Mark 1.0. Free to use for anything.
