"How & Why" Books--intro To Engineering

Q: This came up once before but not much of a response? When I was young, there was a series of books for kids called "How & Why". IIRC, one was on bridges, the other on buildings in general. Others covered all sorts of sciences--electricity, geology, etc. These were an excellent introduction to engineering. I remember the books explaining things like compression strength, shearing strength, and tensile strength, and the ability of different materials. It also disussed the resonance frequency and the Tacama bridge issues. It described a truss vs. cantilever bridge. I had a set but unfortunately they're lost. Does anyone remember these books? Are there any contemporary books for young people that give an introduction to engineering?

A: There was "Bridge and Tunnel," and there was "Girder and Post." I got both

one year, as my birthday and Christmas are two weeks apart. They were incredibly frustrating, because the pieces were held together by tiny tenons on the girders that fit into tiny mortises on the posts, all of which easily broke off; and the diagonal bracings used in building the bridges were strips of plastic with holes in the ends that fit tightly over pegs on the sides of the girders and posts near their ends; the pegs didn't often break off, but the loops on the braces were rather fragile. (They didn't actually make tunnels, so you're right to note that this posting doesn't belong here. Except IIRC the biggest, fanciest set could make a model of the Triboro.)