As related in Science and Polity in France: The Revolutionary and Napoleonic Years, the French had a multi-year program for developing incendiary and explosive shells, principally intended for the navy. Extensive tests with the explosive shells in 1798 at Meudon, using 1794/95 produced ordinance (found to still be reliable and to not have degraded), fired by land batteries against land targets which represented ships of the line, proved to be highly effective, although with the provisos that accuracy was dismal since it was the first time that gunners were firing something other than round shot, so the shells had a tendency to go high. Previous 1794 tests had been carried out by the French ship La Montagne, and had again been quite effective for explosive shells (in both cases, incendiary shells did not work as well): in response some 300,000 shells had been ordered to be manufactured, joining around 5,000 previously constructed prior to 1795. In a battle in 1795, a French frigate was ordered to use its explosive shells by the command of Etienne-François Le Tourneur, and put 3 English ships out of commission at Cape Noli. However, the French Navy displayed little interest in the idea - advocates of the new ordnance claiming it was due to conservatism and fear of obsolescence of its ships of the line, although I suspect it came much more likely from the fear of being blown up by its own shells, an entirely reasonable and justified fear. The Meudon Commission recommended that 10 explosive shells and 5 incendiary shells be provided for each cannon of 36, 24, and 18 pounds, with appropriate instruction on their use and safety procedures. The book does not mention whether this was ever acted upon. But what if it was? What if the French Navy was equipped with explosive shells, and acting upon this perceived gain in combat effectiveness, was ordered to go ahead with its planned invasion of England and engage the Royal Navy in a pitched battle? What would be the effect of the shells on the British? How many French ships would succeed in blowing themselves up with dangerous ordinance on-board? If the French navy did succeed in winning a temporary tactical and operational victory over the Royal Navy, could it go on to invade the UK?