How Locks Work by Carlo Clerici. This features a pin tumbler lock, invented by Linus Yale, Sr. in 1848. Here’s another example in gif format: For more locks, travel back to the 1700s: The Roentgens’ Berlin Secretary Cabinet. Plus: Making a combination lock from a steel bolt. This Webby award-winning video collection exists to help teachers, librarians, and families spark kid wonder and curiosity. TKSST features smarter, more meaningful content than what's usually served up by YouTube's algorithms, and amplifies the creators who make that content. Curated, kid-friendly, independently-published. Support this mission by becoming a sustaining member today.