When Alexander Bell's lawyer heard that Gray had described a vibrating rod in a liquid to vary the resistance, he added a claim for variable resistance in a draft of Bell's unfiled patent application and added an additional seven sentences that mentioned mercury as the liquid.
42.
On February 19, Zenas Fisk Wilber, the patent examiner for both Bell's application and Gray's caveat, noticed that Bell's application claimed the same variable resistance feature described in Gray's caveat, and both described an invention for " transmitting vocal sounds ".
43.
When Gray applied for a patent for the variable resistance telephone transmitter, the variable resistance ) invention, as in his caveat of 14 February 1876, his failure to take any action amounting to completion until others had demonstrated the utility of the invention deprives him of the right to have it considered ."
44.
When Gray applied for a patent for the variable resistance telephone transmitter, the variable resistance ) invention, as in his caveat of 14 February 1876, his failure to take any action amounting to completion until others had demonstrated the utility of the invention deprives him of the right to have it considered ."
45.
"' Paratonia "'or "'gegenhalten "'is defined as " a form of hypertonia with an involuntary variable resistance during passive movement . " In other words, attempting to move the limb of a person with paratonia will result in that person involuntarily resisting the movement.
46.
There is just one external variable resistance that I'm measuring and R 2 is fixed . ( Although if there was a good reason to do it, I could make R 2 be the variable one and R 1 be the fixed resistance . talk ) 03 : 39, 29 October 2013 ( UTC)
47.
In a letter of March 2, 1877, Bell admitted to Gray that he was aware Gray's caveat " had something to do with the vibration of a wire in water [ the variable resistance breakthrough that made the telephone practical ] and therefore conflicted with my patent . " At this time, Gray's caveat was still confidential.
48.
When Bell arrived in Washington on February 26, 1876, Pollok apparently requested that Bell write the seven sentences and other changes onto version F in Bell's handwriting, thereby creating a draft containing the variable resistance feature that Bell could later testify was made before January 18, 1876 " almost at the last moment " before sending version F to his lawyers.
49.
According to Evenson, early on Monday, February 14, after learning of the variable resistance feature from Gray's lawyer, Pollok or Bailey inserted the seven sentences into version X, revised the claims, made other minor revisions, and had the clerk prepare a new engrossed fair copy, version G which consists of 14 pages, not including a signature page.
50.
Though the advisability of using mercury in his device has been questioned, it is Bell's description of how the conducting-wire is immersed ( more or less deeply ), and the effect on electrical resistance that this does have on the passage of current in " other liquid ", that proves his understanding of undulating current and variable resistance in this device, at the time of his patent application.
