Back in time, dog poop was an extremely valuable resource for leather makers. Every coat, handbag, briefcase or any sort of leather goods was created by using dog poop to an extent. So as you can imagine some entrepreneurs around the city of London found a way to benefit from this ever-growing need for dog poop.
They kept the streets and alleyways free of the brown mess because it was worth money when taking to the local tanneries. You see long before the industrial revolution that brought in modern manufacturing and chemicals for cleaning factories, tanneries had such an overpowering smell that they were generally found outside of the city.
But in the city of London, everyone knew that poop was an important part of the tanning process. So this business effectively kept the streets clean because it would be shipped out to the tanneries. You see dog feces contains enzymes that will break down collagen in hides, part of the tanning process which is known as bating. It comes as no surprise that older encyclopedias refer to tanning as a noxious and odoriferous trade.
Skins would arrive in a tannery covered in blood and wet from whatever animal remains would be clinging to them. The process happens as following, first you soak them in water to clean them, then you would soak them in urine which makes them pliable to cut off the hair with knives. And that is when the poo would come into play, it does sound disgusting reading about it now, but back in the day, there were no chemicals available to make your leather shine. The lovely fine leather goods would be achieved by a mixture of water and dog poop. And sometimes they would even use pigeon poop also.
It is funny to think that we now find our streets covered in dog poop, as owners have no reward to pick them up anymore. Sometimes it seems we may have been doing the right thing back in time before the modern age of machinery took over.