Volume 1

5 Apr. 1876

Page 94

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Fig 3 was sensibly thrice if not four times as great as the vibration of p Fig 2 .
4. Apparatus arranged as in Fig 4 page 89. Same receiving instrument employed as is shown in Fig 1.
   P plumbago vibrating in mercury M.
   For lack of a proper stand my father held the transmitter so as to allow the plumbago P to dip into the mercury while Mr. Richardson sang into A.
   The sounds were loudly audible at z.
5. The transmitter was necessarily held unsteadily + great difference in the intensity + quality of the sounds proceeding from z were observed.
   When P was only slightly immersed the sound at z was feebly but every now + then it would suddenly burst forth so loudly as to startle the ear placed at z. At such times my father noticed a bright spark between P + M showing

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Volume 1

5 Apr. 1876

Page 94