The Unclear Bomb is not the Apocrypha
From Fallen London Wiki
Unclear Bombs exist in the setting. They work. The FLPC even uses one, in one Ambition. And since such devices already exist, that begs the question: what's apocryphal about this timeline? What about this vision implies a divergence from our own?
The Apocryphon here is not the bomb. It's the label.
This wasn't made by a couple of mad scientists weirdos locked up in a lab. This was made in a factory, en masse. The calamity Vulgate decided to preserve is the one where unclear bombs become standard military issue for the London navy, and this one is in active use.