Working in Metals by Charles C. Sleffel

This single page illustrates many of the things that have changed since the early 1900's. The second young man is already bored with his job as "elevator operator". Elevator operators were seen in almost every building that had an elevator during this period and for a couple generations more. Then they ceased to exist entirely. Ironically this was also about the time that the general blacksmith (the blacksmith around the corner) would fade from the American scene. And while boys still build things in their bedrooms few have work benches with a vise, torch and metalworking tools. In our paranoid "modern" society many would label this a "bomb maker's bench".

This somewhat distracting side plot of one boy introducing the other into metalworking fades as the book progresses.