Btw, did you know that Jacobs helped Hergé redrawing the backgrounds of some of the Tintin comics after the war? And Leloup (Yoko Tsuno) also worked for Hergé before starting his own series. There is an interview with him on youtube.
Speaking of walls of text, remember the explanation of the inner workings of an atomic reactor in Destination Moon? That's how 5 y.o. me discovered nuclear physics :]
Just checked, you are right. Not only the explanations of the reactor, but from the moment they arrive at the secret research facilities, the dialogs become unusually long. I don't remember well that one, probably skipped the pages as a kid :)
And the series is still going -- the latest book in the series just came out last year. Cinebook is publishing English translations of the series, too.