15 years after Galileo designs a pendulum that could regulate clocks, Dutch astronomer Christiaan Huygens produces the first true pendulum clock.

This technology had massive repercussions for the modern world and led to the invention of the marine chronometer, which increased exploration and brought Charles Darwin to the Galapagos islands, whose findings there helped form the basis of the theory of evolution.

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Maritime navigation is what drove the advancement in our measurement of time. On land, at the time, there was no need for clocks that were accurate to the second, but at sea, sailors were starting to realize that accurate measurement of time was crucial to navigation. Which means that the need for accurate clocks didn’t come from the calendar, it came from the map.

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A 19-year-old Galileo made an observation: “The marvelous property of the pendulum, is that it makes all its vibrations, large or small, in equal times.”

This discovery, the idea of equal time, became one of the foundations of our modern life and contributed to the revolution of time.

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Doctor John Leal was determined to find a way to kill bacteria in water and in 1908, he saw his opportunity after a New Jersey water company was suffering from high bacterial content.

He dosed the drinking supply of 200,000 people with potentially lethal chlorine. Most thought he was a madman for “poisoning” the community, but his experiment proved them wrong and soon a series of developments were made, resulting in a ripple effect of change.

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In 1854, during a deadly outbreak of cholera in Soho, John Snow went door to door recording the deaths and their addresses on a map. He quickly realized the deaths were concentrated around a water pump, and the workers at the local brewery had easily escaped the disease. Ultimately proving that cholera spreads through water.

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Can you believe beer for breakfast was a healthy way to start the day?! That’s right, our ancestors would have several glasses a day! Why? Because the beer brewing process kills disease. So if you live in a dirty part of town, beer was in fact a sensible drink to have.

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Inspired by Chicago, 20 American cities have built their own networks of underground sewer systems, but it didn’t stop there. The creation of these systems led to trash collection, underground transportation, pedestrian walkways, auto freeways, electrical higways and fiberoptic networks. It’s a revolution indeed!

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To keep Chicago clean in the 1850s, engineer Ellis Chesbrough had the incredible idea to lift the city using jack screws.

Buildings, blocks and even neighborhoods were raised10 ft, (some were moved altogether!) to lay angled sewers underneath for draining.

During the process businesses proceeded without interuption, and by 1860, almost an entire acre of buildings, weighing about 35,000 tons, were lifted by more than 6,000 jack screws.

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