What did Marie Brown invent?

Related questions

1. What is CCTV footage?
2. Can my employer record video and audio?
3. Can you watch your staff on CCTV?
4. How long is CCTV footage kept in Ireland?
5. Is CCTV footage considered personal data?
6. Can I be recorded without my permission at work?
7. Do surveillance cameras help prevent crime?
8. Can private CCTV footage be used in court?
9. Do security cameras decrease crime?
10. Are CCTV images personal data?

Tags

1. #brown
2. #famous
3. #forerunner
4. #circuit
5. #invention
6. #brittan
7. #inventor
8. #applied
9. #closed
10. #albert
11. #partner
12. #modern
13. #television
14. #american
15. #patent
16. #system
17. #african
18. #marie
19. #security