Memoirs presented to the Cambridge philosophical society on the occasion of the jubilee of Sir George Gabriel Stokes, bart., Hon. LL. D., Hon. SC. D., Lucasian professor.

192 MESSRS GLAZEBROOK AND LODGE, EXPERIMENTS ON THE OSCILLATORY
Four sparks were taken on each circle.
Circle I. speed inoderately steady. Circle V. speed fair.
II.,, fair. VI.,, steady on average.
III., quite steady for 3 sparks. VII., slightly backing.
IV.,, steady. VIII.,, fair.
To save space only the differences are quoted. All the differences read are included.
Sometimes overlapping prevented any reading being attempted.
The general mean from Table X. is 14~ 28', while the central swings give 14 19'.
These means include all the circles. The range of the mean readings is about the
same as for plate U, and the frequency calculated for the central swings works out
to 1610 oscillations per second.
TABLE XI.
PLATE R. Complete Coil A + B.
Circle... I. I. III. IV. V. VI., VII.
Spark 1 26~ 52' 26~ 53' 26~ 34' 26~ 43' 26~ 47'
26 16 26 22 26 11 26 19 26 23
26 18
26 46
26 44 26 55 26 51 26 52 27 1
26 4 26 18 26 15 26 20 26 23
26 51 27 7
3 26 59 26 51 26 55 26 46
26 4 26 12 26 19
I1 26 50 26 37 O
4 i 1 26 38
26 4
General 260 33' 26~ 30' 26~ 32' 26" 37' 260 37'
Mean
Central 26~ 12' 26~ 15' 26~ 13' 26~ 14' 26~ 21'
Mean
General mean of plate 26~34'.
Mean from central series 26~ 15'.