[D7941ZFX], Letter from Thomas Alva Edison to Edward Hibberd Johnson, October 14th, 1879
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Title
[D7941ZFX], Letter from Thomas Alva Edison to Edward Hibberd Johnson, October 14th, 1879
Editor's Notes
"Rough notes only as they fly through my head" about pat situation. TAE 1st to apply carbon variable resistance to practical inst. Use of induction coil novel; fully explained in final. Bell provides no details for HOW to vary resistance. Clerac, Hughes, Thomson lack printed evidence of earlier use of carbon as Brit law requires. Patent is for practical object, not underlying idea. Even if claims upheld narrowly, diaphragm is only practical way to vary resis. Can't understand how any pat lawyer can assert that the micro (eg Blake) isn't the carbon tel. Can phrasing of claims be altered?
Date from docket, stamp, postmark
Author
Recipient
Mentioned
Date
1879-10-14
Type
Folder/Volume ID
D7941-F
Microfilm ID
52:804
Document ID
D7941ZFX
Publisher
Thomas A. Edison Papers, School of Arts and Sciences, Rutgers University