...that on Dec. 15, 1836, the Patent Office was completely destroyed by fire? Lost were some 7,000 models, 9,000 drawings, and 230 books plus all records of patent applications and grants.
Make the Most of Our Site
See this month's Top Inventors and Most Cited Patents.
Stay on top of the latest innovations by subscribing to an RSS feed.
Registered users: Manage your profile.
| Number | Title | Issue Date |
| 5393970 | Optical location tracking devices A practical location tracking device provides cost-efficient methods for inputting three-dimensional location information. This device comprises light sources and light receiving elements. Each light receiving element comprises two or more closely spaced ... | 02/28/1995 |