"Almost all the magazines had by now been destroyed, excepting the powder magazine, which contained an infinite number of barrels, and which the besieged had taken every imaginable precaution to protect from injury. But it often happens that, in cases deserving such extreme care and attention, the grave fault of omission is committed, and this happened to the besieged in the removal of the powder from the magazine, which was quite bomb-proof owing to the depth of the subterranean chambers in the form of which it was constructed.
It happened one day that a leaky barrel caused the formation of a train of powder leading from the interior of the magazine to the last door outside, without its being noticed by those rolling it along, and this communicated with the powder outside as if it had been laid on purpose. One of our shells, which then chanced to fall just outside the entrance, set light to several barrels standing there, which in their turn lighted the train, and thereby the magazine, which flew skywards with such a terrific explosion that it even created a panic in the enemy's camp outside."--pgs. 330-331, Chronicles of an Old Campaigner by M. De La Colonie.