A D V E N T U R E S in C Y B E R S O U N DAlexander Graham Bell's Laboratory Notebook March 10th, 18761. The improved instrument shown in Fig. I was constructed this morning and tried this evening. P is a brass pipe and W the platinum wire M the mouth piece - and S the armature of the Receiving Instrument.
 Figure 1
I then shouted into M the following sentence: "Mr. Watson - Come here - I want to see you". To my delight he came and declared that he had heard and understood what I said. I asked him to repeat the words. He answered "you said 'Mr. Watson - come here - I want to see you'." We then changed places and I listened at S while Mr. Watson read a few passages from a book into the mouth piece M. It was certainly the case that articulate sounds proceeded from S. The effect was loud but indistinct and muffled. If I had read beforehand the passage given by Mr. Watson I should have recognized every word. As it was I could not make out the sense, but an occasional word here and there was quite distinct. I made out "to" and "out" and "further", and finally the sentence "Mr. Bell Do you understand what I say? DO-YOU-un- der-stand-what-I-say" came quite clearly and intelligibly. No sound was audible when the armature was removed. 2. The effect was not increased by increasing the power of the battery. The maximum loudness was obtained with two cells. 3. When more than two cells of battery were employed the escape of gas at the wire, W, was so violent as to cause the wire to vibrate. upon listening at M the noise of the effervescence was perfectly deafening. The sound was audible from S also but in a lesser degree. No sound was audible from the Receiving Inst. when the spring S was removed. When sounds were uttered into M by Mr. Watson they were audible at S in addition to the hissing sound due to the escape of gas at W. 4. The pipe P being of brass and the wire W of platinum the arrangement constituted in reality a battery. A black deposit formed upon W which had to be removed every minute or two. 5. The acidulated water was caused to splash up against the membrane by the vibration of W and the membrane soon ceased to respond to the voice until tightened. 6. The more deeply the point P of the tuning-fork f (Fig 2) was immersed in the water the feebler the sound from S.
 Figure 2
8. Two tuning forks A and C pitched respectively to A + C were simultaneously sounded and presented to the water (Fig 3). Both sounds were audible at S.
 Figure 3
 Figure 4
(Thoughts) 10. The metals P and W (Fig 1) must be the same to avoid converting the arrangement into a battery. 11. The indistinct and muffled effect of the articulation is probably due to the imperfection of the Receiving Instrument. The spring S was pressed so slosely between the ear and the pole of the magnet that it had no room for vibration. Fig 4/2 shows new form of receiver to be constructed.
 Figure 4/2
Noted by A.G.B. G.G.H. and M.G.H. March 12th 1876
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