Weird books for tinkerers and mad scientists

I came across an ad for Lindsay's Technical Books in Popular Science. The ad reads like a classified that would have been in the back of the magazine fifty years ago: "Secrets! Melt Metal! Machine Shop! Hydrogen! Old Time Radio! Tesla! Chemistry! Incredible plans, lost secrets, forgotten how-to, and strange books!" It looks like these folks have a lot of fun in their basement labs and backyard foundries. Link