Before Blake & Mortimer Tome 2
The Fiery Arrow

The Marduk expedition has returned victorious to Norlandia, bearing a precious sample of Uradium. Now the professor can test his revolutionary U Ray's potency when combined with the miracle ore. But Austradia, the old enemy, won't take this lying down. So the dastardly Captain Dagon didn't succeed in stopping Marduk from finding the Uradium deposit? No matter! The Imperial Austradian Army will simply take possession of it in a military operation - and who cares if that's where Prince Nazca's people live? The eminent Professor Marduk is tasked by the High Council of Norlandia with militarising a major scientific discovery: the U Ray.
However, doing so will require finding a deposit of Uradium, the ore needed to power the ray. And the only known deposit is in an unexplored volcanic archipelago. An expedition is quickly put together, but in the shadows, the Austradian intelligence services are waiting for the moment to act .