How, When, and Why Were Pink Erasers Added to Pencil Ends?
17:23
Cómo escribir con pluma
8:52
Who Invented ‘Duct’ Tape, or is it ‘Duck’ Tape? - Find out in this episode
11:43
Escribí un diario durante 10.000 días. Así es como lo hago ahora
8:20
Why Are Pencils Painted Yellow?
23:21
The Numitron: An obvious idea that wasn't very bright
10:08
La historia de las plumas estilográficas: una breve historia
22:47
The invention that broke English spelling
35:13