Hot water balloon
Commissionment by Napoleon II Jr
In 1822, in order to spur the French effort to bring France into the 17th Century, the Emperor Napoleon II Jr (after having learned about the theory of buoyancy from the notoriously accurate Uncyclopedia Française) commissioned the famous Corsican inventor duo Le Cheech & La Chong to design and build the world's first ever hot water balloon using nothing but a partially-decomposed ram's bladder and copious quantities of duct tape.
Researchment and test flightment
The inventive brothers spent many years testing and retesting the reinforced cylindrical container for structural defects the only way they knew how, with the assistance of a battalion of leggy mademoiselles (at 10 francs per shot). Finally, the thoroughly exhausted inventors, having run fresh out of francs on 14 July 1839, inflated the device with thousands and thousands of gallons of boiling-hot water and launched themselves off of the pointy tippy-top of the Eiffel Tower.
After floating majestically in the warm sunny afternoon breeze for a full 0.002 seconds, a loosened strand of duct tape accidentally snagged the tower's television antenna and ruptured the balloon, releasing a tidal wave which simultaneously drowned and cooked the entire population of Paris. A few days later, the remnants of the emptied balloon itself inexplicably burst into flames, adding to the irony. Oh well, as the French say, C'est la vie.
And now, the conspiracy theory
A few soggy survivors of the disaster have sworn in a legal deposition that they thought they saw somebody taking a pot shot at the Chong Brothers's balloon with a cannon from a nearby grassy knoll. Most of them also claimed that the perpetrator then entered a White Fiat Uno and headed in the general direction of Paris. However, their testimony is considered utterly worthless today, since these alleged witnesses have been dead for quite some time now.
Today's modern hot water balloon: a nifty toy for the kiddies
In these enlightened times, the horrific tragedy is re-enacted every Bastille Day by young French children filling up as many as ninety-nine red toy balloons with microwave-heated Perrier™ and flinging them at each other.