Mad About Science: Toilets

By Brenden Bobby
Reader Columnist

There is one universal truth about Thanksgiving: what goes in, must come out. Poop is gross, but at least we live in an age of controlled bodily waste. During the first Thanksgiving, it was likely that the waste of the feast ended up in one of two places: a chamber pot or secluded spot to squat.

It turns out that the pilgrims didn’t spend a lot of time writing about where their poop went. To be fair, aside from the occasional emoji, do you chronicle your bowel movements for future historians to analyze? We know they used chamber pots during their voyage on the Mayflower. Chamber pots were large pots you squatted over to do your business, which you would theoretically empty once you were done. Sometimes they had lids, other times they didn’t.

I can’t account for the location of chamber pots on the Mayflower, but it was common practice for large sailing vessels of the day to have an area near the prow where sailors could do their business and send it into the sea. This is the origin of the term “the head,” as these maritime waste evacuations would occur at the head of the ship. 

The first flushing-rim toilet made its debut in 1824. Courtesy photo.

There was a very specific reason for the placement of this facility. If it were placed at the back of the ship, the wind filling the sails would also push a persistent smell across the entire deck of the ship for the duration of the journey. If the facility was at the front of the ship, the wind was always blowing the smell out to sea and away from the crew and passengers.

Personally, I think this is a much more intelligent solution than a chamber pot on a boat, as anyone who was feeling particularly lazy ahead of a storm would face an unfortunate spill or splatter during rough seas. Rancid smells were unavoidable on the Mayflower, regardless of the fastidiousness of the pilgrims. Rats were commonplace on sailing vessels, and they pooped, too, spreading bacterial diseases like leptospirosis to the humans onboard. The Mayflower was anything but a pleasure cruise.

Once the pilgrims landed, it’s likely that dealing with waste became a little more difficult than at sea. You can compost human waste, but doing so runs the risk of spreading communal diseases to your crops through bacteria in the waste — this is particularly true when applied to root vegetables, which directly absorb and store nutrients and other hitchhikers directly into the edible part of the plant. Similarly, dumping waste into the ocean from the shore will likely just result in your effluvia washing back onto the beach, with sea winds pushing the smell right at you.

Compared to the pilgrims, we live a pretty good life. The first modern flush toilet was described in 1596 by John Harington, godson of Queen Elizabeth I. Harington is the reason we refer to toilets as “Johns” to this day. 

Prior to that, the ancient Romans were believed to have used flowing water routed from aqueducts to create a constant flow at communal toilets. They saw pooping as a social event, and an opportunity to catch up with your neighbors on recent events and politics.

Notably, early toilets lacked the tanks that most home toilets have today. This particular innovation wouldn’t become widespread until 1902, though it still used up to seven gallons of water per flush and required a gravity feed from a spring in order to use. Over time, toilets became more efficient at using less water. Today, they use around 1.5 gallons per flush.

The premise of a toilet is fairly simple, but the mathematics behind it are very involved. There’s a reason it took so long for people to develop the kinds of toilets we use today.

Your toilet consists of two major components: the tank and the bowl. Pushing the lever on the tank opens the flush valve at the bottom of the tank, which sends the water from the tank flowing down into the bowl. This change in pressure causes a siphon to occur, pulling your waste into the siphon tube, which then directs it to the sewer or your septic tank. A water supply line refills your toilet’s tank and, after a certain point, a float ball attached to the flush arm will be pushed up and into a neutral position by the rising water. This will seal the water supply tube and also the flush valve, resetting the toilet and letting you know it’s prepared for another use.

If there is a defect with your flush valve or something isn’t quite calibrated properly, your toilet might continue to run. You’ll hear water flowing in from the supply line and you’ll notice the water in the bowl is moving. Luckily, there’s an overflow tube that sits just above the float ball that collects excess water and prevents your toilet from overflowing at the tank. You’ll want to correct whatever is wrong with your toilet, however, because this will end up costing you a lot of money if you just let it run indefinitely.

The last bit of toilet trivia I’ll leave you with is this: Have you ever wondered what the deal is with reading on the toilet? Apparently during the early 1900s, rather than having dedicated toilet paper, folks would collect magazines and newspapers to wipe with when they were done. I wouldn’t recommend trying that after reading on your phone.

Stay curious, 7B.