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Santa and his reindeer didn’t appear in the sky immediately upon the birth of Christ, and the Christmas holiday as Americans now know it—the carols, the lights, the long-distance travel, and, above all, the massive consumer spending on gifts—didn’t always exist this way. By the mid-1800s, the holiday had picked up and assimilated various elements of European religious and pagan traditions. Upon the publication of Charles Dickens’s A Christmas Carol in England in 1843, it took a form recognizable to modern eyes.

Despite the enthusiasm for Christmas abroad, the holiday wasn’t all that popular yet in the United States. “They made more of New Year’s than of Christmas,” 101-year-old Jane Ann Brown told The New York Times in 1894. Brown had seen the holiday change over the course of her long life. Unlike today, New Yorkers of her youth didn’t think much of Christmas. What she might not have realized was how much of the holiday’s evolution was attributable to the steel rails multiplying across the American continent.

I am a materials scientist—I study the substances that humans use to construct the physical world we inhabit. How inventors transform materials is widely understood, but less evident—sometimes to the inventors themselves—is the extent to which those materials shape the culture that comes to depend upon them. It’s obvious how smartphones and broadband internet are radically transforming the lives and customs of the people who use them. The cultural alchemy that turned steel into Christmas has been largely forgotten, but today’s holiday is unmistakably a product of innovations in materials.

The creators of the modern American Christmas include such figures as Thomas Nast, whose Harper’s Weekly illustrations gave us our enduring image of Santa, and Clement Clarke Moore, the author of the poem “A Visit From St. Nick.” But just as important was Henry Bessemer, the Englishman who figured out how to make steel rapidly, cheaply, and abundantly. The production of this highly useful alloy requires the careful control of iron and carbon. Bessemer created a quick method to remove carbon from a crude form of iron so that a precise amount of carbon could then be added to the iron to make steel. In 1884, Science magazine declared that Henry Bessemer’s process was “an invention which has, in the short space of a quarter of a century, completely revolutionized some of the greatest of human industries.”

Bessemer’s process made the rails possible, which helped diffuse products across the nation, moving us away from buying only those goods that were locally available. The rails grew at a precipitous rate in the United States. In 1840, before the Bessemer process, there were 3,326 miles of railroad tracks. Just 20 years later, there were 30,600 miles—a little more than the distance around the equator. By 1900, there were enough steel rails stretching across American territory to circle the world 10 times. This meant that almost every corner of the United States was connected; along with that access came the nation’s appetite for that region’s products.

This article was adapted from The Alchemy of Us: How Humans and Matter Transformed One Another, by Ainissa Ramirez.

As factories churned out products, textiles, goods, foods, and materials, the United States went from a state of scarcity and entered the world of excess, as the historian Penne Restad has noted. Companies needed a way to offload all those materials. But for citizens to buy them, they had to be encouraged, because scarcity was connected to morality. The Puritan mind-set of “a penny saved is a penny earned” had to be transformed into an equally pious notion of sharing. The Christmas holiday made the purchase of excess acceptable by combining capitalism with the charity of gift-giving. And with that, gifts evolved into a new language of connection, particularly as families spread across the country. The technology of steel rails was highly useful in transmitting those messages of love through the movement of packages.

Of course, the trains brought fear at first. Some passengers wondered if going 30 miles an hour would strip them of their souls. But the economic benefits of mobility proved too great for the public to resist. Steel also played a role in nurturing Americans’ desire to consume by enabling the evolution of department stores. Department stores, which were later made tall by steel girders, became what Restad has described as “cathedrals of desire.” Their number blossomed in the 1800s. Those who could not make it to stores could acquire items by ordering them through catalogs. With this new convenience, the post office became inundated with packages arriving by train. When Christmas approaches, the Times reported in 1890, the post office clerk “groans."

The pieces of Christmas became stitched together into a mammoth tapestry. First came the Christmas tree, the selling of which became a big business in the 19th century. “There is now in progress a market where competition is as sharp and dealing as close as can be found in any mercantile exchanges,” the Times reported in 1893. “This market deals only in Christmas trees.” From early December until Christmas Day, dealers from Maine sold trees in cities. Those Christmas trees were hauled by train from Maine to New York City on rails of steel.

Along with the Christmas tree came the Christmas card. “Why four years ago a Christmas card was a rare thing,” one postal official said in a 1882 newspaper article that Restad unearthed. “The public then got the mania and the business seems to be getting larger every year.” The last ingredient in the holiday concoction was the tradition of giving gifts. A Times article in 1890 declared “an epidemic in giving and receiving presents.” Not everyone was happy with how Christmas was going. “It seems the fashion to be extravagant, almost reckless, in expenditure,” said the Times in 1880. “People of all classes vie with each other in the costliness of their presents.” Despite these virtuous sentiments, society’s view was propelled by trains full of Christmas trees, Christmas cards, and Christmas gifts, all moving on the railroad’s steel tracks.

This winter holiday evolved to serve as a connector of a sprawling country. Shopping was part of the American culture, and the steel rails enabled shopping. The trains brought in the products and the trains brought people to the stores to buy these products, creating a circulatory system. Christmas provided the rapid pulse.

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