This is from a book in the book. But that was written in German, and translated by the protagonist into English – in a know-yur-vanquisht-enemy way.
So then: what grandious German word would the author hav used here? »Erschütterung«? Sounds a bit weak for »boulversement«. Maybe Henry pickt that to get the general blustering haughty tone of the tome, rather than to match a single word.