On Nov. 15, 1895, at noon in London near Fenchurch Street, as reported in the London Morning Post the next day, an “‘alarming explosion’ occurred. No damage was done; no trace could be found of anything that had exploded. An hour later, near the Mansion House, which is not far from Fenchurch Street, occurred a still more violent explosion. The streets filled with persons who had run from buildings, and there was investigation, but not a trace could be found of anything that had exploded. It is said that somebody saw ‘something falling.’”
Although nothing was found, the police (‘deadly explainers’) explanation was that “somebody had mischievously placed in the streets fog-signals, which had been exploded by passing vehicles.”
–Charles Fort, New Lands, p468 (The Complete Books of Charles Fort, Dover, c1974).