+-------------------------------------------------------------+ |No. of specimen.| Galvanometric deflection. |Ratio b/a.| | +---------------------------------+ | | | (_a_) at 45° | (_b_) at 90° | | +----------------+---------------+-----------------+----------+ | 1 | 70 divisions | 110 divisions | 1·5 | | 2 | 30 " | 45 " | 1·5 | | 3 | 90 " | 126 " | 1·4 | | 4 | 70 " | 100 " | 1·4 | | 5 | 21 " | 33 " | 1·6 | | 6 | 30 " | 50 " | 1·6 | | 7 | 12 " | 20 " | 1·6 | | 8 | 14 " | 20 " | 1·4 | | 9 | 10 " | 16 " | 1·6 | | 10 | 45 " | 75 " | 1·5 | | 11 | 25 " | 40 " | 1·6 | | 12 | 14 " | 20 " | 1·4 | | 13 | 13 " | 20 " | 1·5 | | 14 | 30 " | 50 " | 1·5 | | 15 | 38 " | 54 " | 1·4 | | 16 | 50 " | 75 " | 1·5 | | 17 | 55 " | 90 " | 1·5 | | 18 | 13 " | 20 " | 1·5 | | 19 | 17 " | 25 " | 1·4 | | 20 | 80 " | 130 " | 1·5 | | 21 | 15 " | 22 " | 1·4 | | 22 | 45 " | 75 " | 1·5 | | 23 |135 " | 220 " | 1·6 | | 24 | 55 " | 93 " | 1·5 | +-------------------------------------------------------------+ | Mean ratio = 1·49 | +-------------------------------------------------------------+ The mean ratio 1·49 may thus be regarded as the relative geotropic effects at 90° and 45°; this is practically the same as Sin 90°/Sin 45° = 1·4. Hence we arrive at the following law: _The intensity on geotropic action varies as the sine of the directive angle._ METHOD OF VERTICAL ROTATION.