TIL that the explosion of Mount Tambora in 1815 led to the invention of the bicycle.
When the eruption of the volcano resulted in the "Year Without Summer" in Europe, which caused a famine, many folks had to euthanize their horses, because they couldn't feed them and/or to eat them. A German invented a wheeled device that he thought could replace the horse for personal transportation. He called it a "Laufmaschine", but it's sometimes called a "velocipede", "dandy horse", or "hobby horse." It looks a bit like a bicycle without pedals, but it functions more like a scooter, where you propel yourself with your feet and then coast for a bit. The early ones were made of wood, steel and leather, and weighed ~50 lbs / 23 kg. Then in the 1860s, a French engineer decided to put a crank and foot pedals on it. Et voila. Eruption of Mt. Tambora -> bicycles.
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TIL that the can opener followed the tin can by a couple of decades. For a long time, cans of food had to be opened with a hammer and chisel, a hatchet or a bayonet (canned food was initially invented for armies on the march). In many places, where civilians weren't carrying entrenching tools around with them, the shop owner would open the can for you when you bought it, and you'd carry it home open.
p.s. The design of the can itself is pretty much unchanged. The only real innovations in food cans has been the "pull to open" pull-tab, the material the can is made of, and the machinery that can produce, fill and seal vast numbers of cans. If you found a food can from 1840 with the label removed, you'd just think it felt a little heavy.