There's a scene that has had me bothered for years. In "Explorers", when Calculus, Haddock and the Thom(p)sons set off in the tank, Calculus announces that it is to explore the cave where they expect to find radium or uranium. When he talks to them on the radio, Tintin states that he is going to mend "the radios on our space-suits".
How did they know that there were radium or uranium deposits in the cave? and only Snowy's radio was damaged in the incident so why "radios" as in plural? It's a couple of issues that had me scratching my head for decades. (One of these days, my penchant for getting every detail right will drive me crazy: prepare to change my username to "Rameses II".)
Recently, I read the story in copies of
Tintin magazine from the 1950s which included scenes not included in the book:
When Tintin and Haddock enter the cave they are carrying guns (
debated here) and large green boxes. A panel not included in the book shows that these are Geiger counters and Haddock points out that they are reacting furiously to radioactive material.
The cave incident includes a couple of pages with extra scenes: Haddock cannot lower the rope enough to reach the ice so Tintin picks Snowy up in order to tie him to the rope only to lose his balance and again fall down the sheet of ice, dragging the rope with him.
This time, Tintin's radio is damaged and he cannot talk to Haddock any more. He remarks to Snowy that they are probably doomed to perish, but then climbs back up the ice. He tries to lasso a ledge but fails.
Then he sees another rope coming down with a stone attached to it. Tintin even exclaims "But... but... am I dreaming?", somewhat astonished that Haddock even thought of going back to the tank for another rope and lowering it to him.
Tintin ties Snowy to the rope and Haddock gets him out but then the stone gets caught on a ledge and Tintin is panicking because it is not returning and he cannot communicate with Haddock.
Adds extra tension, what with both radios being unusable, and explains my query.