"Yes, sir; I can hear you," came his voice from the speaker.
"Can you hear your own voice?"
"Yes, sir."
"Very well. Now, are you watching what Mr. Oak is doing?"
"Yes, sir."
I picked up a small ball-peen hammer and hit the speaker--not too
gently--at just the right place.
"Did you see that, McGuire?" I asked.
"Yes, sir. I saw it." His voice sounded hoarse, muffled, and whispery
coming through the damaged speaker.
"Do you see what sudden damage can do to speaking apparatus?"
"I must test," McGuire said, an almost hesitant note in his new voice.
He spent fifteen seconds or so saying a series of nonsense syllables
that are used as a test for a robot's speaking apparatus. They contain
every sound used in English.
When that was over, he said: "The damage inflicted has radically
changed the basic patterns of the voice. If an equivalent amount of
damage was done to Mr. Oak's vocal apparatus, then the voice which has
been speaking must belong to Mr. Oak."
"You saw the damage being done in each case," I said quickly. "You also
see that it is the source of the voice that becomes important when the
pattern has changed."
"Yes, Mr. Oak. I see that."