A humble paper product tells a story of farming, waste, and home technology in 19th- and 20th-century America.

Reuters

The square-shaped, flat-bottomed milk carton: It has always worked for me, even if I haven't entirely mastered the pinching-pulling motion required to open the top, and often mutilate the carton's spout.

Imagine my surprise, then, when I traveled to Uruguay and discovered that its milk only comes in plastic bags. Non-resealable ones! Ones you cut open at the corner! So that after you use the bag for the first time, it flops around the refrigerator, spilling milk all over the apartment!

Citizens of the U.S.A., I have returned from that land of 3 million people and 10 million cows to tell you that there is another way. The non-resealable plastic bag: it causes less waste than cartons. Also: it is a form of behavioral control to get you to drink the milk really fast so it does not go bad. When you are full of milk and don't want any more, you seat the bag gently in this little plastic pitcher that is in the back of your cabinet (your landlord may have forgotten to mention this to you). The little plastic pitcher has a flat bottom and can go in the fridge.

And yet. I started to think about the brave tale of our U.S.A. milk cartons. Enter: History!

Library of Congress

Remember what I said about milk going bad really quickly? That has been true for hundreds, maybe thousands of years. Historically, nature has dealt with the problem by storing the milk in the cow.

However, not all of us own a cow. Farming was invented so we would not have to. Farmers pull the milk out of cows so you can drink it. (Or they used to.)

Actually, in the United States, a lot of rural people still owned cows into the late 19th century. To provide milk to town and city people -- a population that grew rapidly starting around the time of the Industrial Revolution -- dairy farms, generally small ones, at this point, hand-milked cows and put the products into glass bottles, which were then delivered to customers.

A farmer and his cow. So cute, I will not make a joke. (Library of Congress)

When farmers turned to mechanized milking at the beginning of the 20th century, some of the small farms got bigger, and production increased.

Here's the thing. Refrigeration didn't exist yet, unless you count the very ancient icebox, which you shouldn't. The icebox cost a lot to maintain and was inefficient -- because, as the name implies, it was basically an insulated box you put ice in, and ice tends to melt. And: glass doesn't insulate well.

This made milk going bad a problem. And you know what? No one had a good solution to the problem for a while! The best they could come up with was getting a milkman to bring fresh milk every single day and take away the empty glass bottles. This meant everyone always had fresh milk, but it also meant a family had to drink all the milk they ordered pretty fast, or else. It meant a lot of milk!

Library of Congress

Weirdly -- although the existence of one doesn't depend, really, on the existence of the other -- the refrigerator and the milk carton developed in parallel. The first refrigerators were tested in the 1910s. Meanwhile, the inventor of the milk carton (warning: this title is disputed by about a million people) took out his patent in 1915.

His name was John Van Wormer and his milk carton was basically the same as the one we use today. It's called a gable-top, in reference to the innovation of the spout temporarily glued into a ridge and unleashed by that weird pinching-pulling motion that I referred to earlier. The gable-top makes a pretty efficient use of materials, which also means you can produce it quickly. (The milk carton does not need a cap, you might note.) Van Wormer produced his original milk cartons in paperboard. And so they are today, but generally with a slick polyethylene coating, so they don't become vaguely wet to the touch once the milk soaks through.

As with the refrigerator, it took the milk carton two or three decades to catch on. People had become attached to their glass milk bottles.

Emotions be damned, here is the thing. Glass is heavy. The weight of the bottle makes up a total of a third of the weight of a unit of milk packaged in glass (yes, sometimes they still are!). Hey, and you know what? Hauling giant bricks of ice around to put into an icebox is a huge drag!

Reuters

Refrigerators got cheaper, and, for better or worse (probably worse), people got used to the idea of throwing packaging away. By the 50s -- that decade of wholesomeness -- most moms would take their several-day-old-milk out of the refrigerator when they wanted to feed their children cereal. But cereal, my friend, is another story.

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