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.

180 MESSRS GLAZEBROOK AND LODGE, EXPERIMENTS ON THE OSCILLATORY
TABLE VII. using only one coil.
Frequency Frequency
Date Condenser Capacity calculated observed
232
Aug. 3 Paraffin condenser 3000 233 230
Glass condenser 190 926 820
237 827
Considering the nature of the experiments the agreement may be considered satisfactory. The capacity taken for the cylinder condenser is probably too high; if it were
assumed as 5'1 instead of 5'5 the agreement in all the experiments in which it was
used would be improved. It is also clear that the value 190 taken for the capacity of
the glass condenser is too small; only one determination of this was made, and there
may have been some leak which reduced the capacity as measured; an earlier attempt
at measuring the capacity was a failure from this cause.
It will be noticed that the corrections have been applied as though on July 24
and 25 the coil connexions were those shewn in Figure 5, while on the other days they
were those of Figure 3. There is no evidence in the note-book that this was the case;
at the time these experiments were made the importance of the direction in which the
current traversed the coils was not realized.
The results of three of the preliminary experiments are not recorded in the table.
On August 1, with the cylinder and disc condensers in use, the connexions were
as shewn in Figure 9, and the frequency was 1766; this result is given.
Spark gap
Earth
FIG. 9.
The connexions were then altered so that the condenser was to the terminals B