At 32 seconds.
37 seconds.
43.5 seconds.
49 seconds.
54.5 seconds.
61.5 seconds.
61.5 - 32 = 29.5.
29.5 ÷ 5 = 5.9 = time of one interval.
_Résumé._
1 5.9
2 6.2
3 6.2
4 6.2
----
Mean = 6.13 = time of one interval between coincidences.
In this time the watch makes 6.13×5 = 30.65 beats, and the forks make
30.65 + 1 = 31.65 beats.
Hence the number of beats per second is 31.65 ÷ 6.13 = 5.163.
_Specimen._
Circumstances the same as in last case, except that standard Vt₃ fork was
allowed to trace its record on the lampblacked paper, as in finding its
rate of vibration.