My grandma is kind of dating this guy (gross right?!), well he's a super old retired machinist. My dad and I both work at a machine shop, him being the lead of inspection (former machinist), me a machinist out on the floor. Well Christmas Eve was at our house this year and he brought over a ziplock bag with two books in it for my dad. That bag contained a Machinery Handbook 2nd Edition! That book is from the mid-late 1910's! We're currently on the 29th edition and it's at least 2.5 times the thickness of this 2nd edition. The second book was a brochure for machinist tools. Depth mics for $3.25.... Nice current day depth mics are $200+! I'm a nerd and so is my dad. We're probably way more excited about than we should be about this stuff haha. I'll post pictures of it all tomorrow after family festivities.