Telephone Call-Signal, April 30, 1878
Item
- Title
- Telephone Call-Signal, April 30, 1878
- Author
- Thomas A. Edison
- Date Executed
- 1878-02-28
- Date Filed
- 1878-03-04
- Date Issued
- 1878-04-30
- Type
- Patent Issued
- Subject
- Telegraphy and Telephony
- Document ID
- PAT203017
- Has Format
- https://iiif.archive.org/iiif/edisonpatent203017/manifest.json
- Rights
- Edison's patents are in the public domain and have been made available through the generosity of David Kovanen.
- Publisher
- The Thomas A. Edison Papers