|Potato was not eaten in France before the Revolution because people believed it either to be poisonous or suitable only for animal feed. Even in Britain, it was scarcely eaten in the 18th Century. People thought it was either a medicament or even an aphrodisiac. There is a remarkable line in Shakespeare’s “Merry Wives of Windsor” where Falstaff, who believes wrongly of course, that he has persuaded two women to share his bed, looks adoringly upwards as he says, “Let the sky rain potatoes!” Many Shakespeare scholars have been baffled by that, but basically what he is saying is send me some Viagra down from the sky! Well, I have eaten lots of potatoes, and I have to tell you… Potatoes were first planted after the Revolution in the gardens there and they had a clever trick, which is to put guards on the garden during the day, and then remove them at night, so the peasants would come, the local would come and steal the potatoes and plant them in their own plots, and the potato very quickly sped through France, vastly increasing French numbers and French health, so that was very clever.
If you look slightly to the east, you can see the hill of Montmartre, and that was the place where, just after the Revolution, the speed of light was measured for the first time.
The person involved, Fizeau his name was, passed a powerful beam from his laboratory, just south of the Tower, to the top of the hill of Montmartre, where there was a mirror where it was bounced back, and in front of his detection device in his own laboratory, he had a spinning wheel, with cogs in it, and he speeded it up and speeded it up and speeded it up until, suddenly, the light stopped coming back, and that is because, in the micro-second it took to get to Montmartre and back again, the next cog had come into view and blocked it. From that, he worked out the speed of light, remarkably accurately. So that is something else which perhaps most people do not realise that is actually something that happened in Paris in roughly those days.