Henri de Blowitz is a character in 80 Days. A journalist working as a foreign correspondent for The Times, de Blowitz is also travelling the globe in search of a story. He is a major part of the Roving Reporter achievement.
Passepartout first meets de Blowitz on the observation deck of the Istanbul-bound line of the Orient Express. If the player helps de Blowitz with his bags and follows him to the dining car, he will discuss the rising political tensions between the Ottoman and Austro-Hungarian Empires.
Passepartout next finds de Blowitz in the souk in Cairo. Continuing his investigation, de Blowitz has discovered that the Ottomans are building a massive automaton to help them invade the Austro-Hungarian Empire, and asks Passepartout too keep an eye out for it during his travels.
A similar automaton can be located in Aswan, where Passepartout finds a gigantic unmanned statue of the goddess Aswan roaming the streets enforcing a curfew. Travelling to nearby Wadi Halfa, Passepartout can telegraph de Blowitz editor and land the story on the front page of The Times. During the player's next journey, the article can be read in the newspaper (credited as "roving reporter") and de Blowitz will send a £2000 reward.
However, the actual invasion weapon that De Blowitz was likely referring to was the Khodunki, a war-machine being built in Herat.