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Leonardo’s Horse

Fall 1991 | Volume 7 |  Issue 2

BETHLEHEM, PA.: Approximately 150 historians, art scholars, and engineers assembled at Lehigh University in Bethlehem last April. The reason? They were there to see a man about a horse. The horse was the Sforza Monument, a twenty-four-foot bronze equestrian statue that was designed by Leonardo da Vinci but never constructed. The man was Charles C. Dent, a retired airline pilot in Fogelsville, Pennsylvania, who hopes to remedy that omission five centuries later by building a full-size replica. At the conference scholars examined historical and cultural aspects of the horse’s original design and discussed how best to replicate it.

Leonardo’s design called for a trotting horse, with diagonally opposed legs raised from the ground, straddled by Francesco Sforza, the founder of a Milanese ruling family. The statue would have been hollow, with bronze skin roughly an inch and a half thick, and would have weighed upward of 130,000 pounds, not counting the rider. Leonardo eventually built a full-size clay model of the horse, but high-spirited French soldiers destroyed it in 1499 by using it for target practice.

Francesco’s son Lodovico, the Duke of Milan, commissioned the statue in 1482 as a monument to his father. Its ostensible purpose was to inspire the public with Francesco’s great deeds of heroism. But as Virginia Bush, an art historian, pointed out, the real reason was to solidify Lodovico’s shaky claim to the throne by amplifying his father’s reputation. (Such multiple motivations for public works are not unknown today.) Leonardo worked on the design on and off for over a decade, but by the late 1480s the duke was expressing doubts about Leonardo’s ability to complete the project. He had good reason to be skeptical.

In the first place, it was impossible. Since each leg could have supported a maximum of about twelve thousand pounds, the statue never would have held up. A life-size model could have stood on four legs, but tripling the height would increase the weight by a factor of twenty-seven while increasing the leg’s cross-sectional area by only nine. (These artistic problems of scale persisted into the 1950s, when such movies as Them! implausibly showed gigantic radioactive mutant ants with the same spindly legs seen on their normal-size cousins.)


Beyond the matter of structural impossibility, Leonardo faced other difficulties. He planned to cast the horse in a single piece, with a mold buried in the ground. Even if he could have overcome the logistical problems of moving and pouring 130,000 pounds of molten bronze, the mold would have been seriously damaged by the enormous pressures inside. In addition, Leonardo had no effective way to exclude moisture from the sand and clay used to form the mold. Even a few droplets, when heated to the melting point of bronze, could cause large bubbles, distortion of the figure, or dangerous explosions. And the heat buildup, particularly at convexities such as the horse’s neck, would have been far beyond what the technology of the day was equipped to handle. Renaissance founders knew how to deal with all these problems on a small scale, but the consensus at the conference was that the Duke of Milan was right: such a huge project would have outstripped the capabilities of even a genius like Leonardo.

Richard F. Polich of Tallix Morris Singer, a foundry in Beacon, New York, reviewed these difficulties and explained how his firm could construct the horse using modern techniques. He envisioned casting it in at least ten pieces. The weight would be reduced considerably by using bronze skin only three-eighths of an inch thick, and the structure would be reinforced with stainless-steel tubing in the legs and an internal skeleton of steel rods to balance the static stresses.

A full-scale replica of the horse, complete with rider, has already been built in Japan out of fiber-glass-reinforced plastic. Hidemichi Tanaka of Tohoku University explained how his group started with a one-third-size model. With a laser device they converted the model’s shape into digital form, and then they used a computer to enlarge it and guide the construction of the full-size horse. Leonardo, lacking the tools to build computers and lasers (he presumably thought of them, as he did everything else), spent years studying live horses, measuring proportions and drawing each part from every conceivable angle. Tanaka’s group, by contrast, built its horse, start to finish, in a year and a half.

Historians of technology discuss Renaissance cast bronze at LehighUniversity and molded Jell-O at the Smithsonian Institution.

Along with these contrasts between Leonardo’s era and today, many similarities were also brought out at the conference. Martin Kemp of the University of St. Andrews in Scotland read excerpts from Leonardo’s notebooks in which he griped about not being paid enough and complained that his client did not appreciate how much work was involved. And W. Chandler Kirwin of the University of Guelph in Ontario told how the ever-present wars of Renaissance Europe was intertwined with the horse’s fate.

Leonardo gained much of his early reputation as a military engineer, and in his initial letter to the duke he listed nine types of military projects he was skilled at before saying in the last line, almost as an afterthought, “Moreover, work could be undertaken on the bronze horse.” He first learned about casting from manufacturing cannon. It was with nice symmetry, then, that the horse project was finally canceled in 1494, when the duke decided that the bronze set aside for it was needed elsewhere—to make artillery for his war with Charles VHI of France. It would not be the last time that military demands scuttled a civilian project.

Dent’s group has built an eight-foot clay model of the horse and is hunting for donors, looking at foundry candidates, and negotiating with the Italian government. They hope to install the horse (without rider) in the Sforza castle’s courtyard by 1993, five hundred years after Leonardo’s clay model was unveiled.

If they are successful, many Renaissance-art scholars will be overjoyed. Yet the project is just as significant from a technological standpoint. Several of the greatest scientists and engineers spent years on schemes that proved to be impractical—Edison with his direct-current power network, Isambard Brunei with the mammoth steamship Great Eastern , even Einstein with his attempt at a unified field theory. Such failures may not have the importance in modern technology that their successes have, but to historians they are equally informative. The Sforza Monument, originally planned to glorify a fifteenth-century autocrat, now largely forgotten, will instead pay tribute to Leonardo da Vinci, who lacked the duke’s money and political power but whose achievements ended up being vastly more influential and enduring.

WASHINGTON, D.C.: The Nation’s Attic became The Nation’s Kitchenette for a day last April as the Smithsonian Institution’s National Museum of American History (NMAH) conducted a scholarly examination of Jell-O. The museum’s staff chewed the subject over and responded with almost a score of papers on topics ranging from vodka Jell-O cubes and Jell-O wrestling to Jell-O and Jack Benny. When it was over, participants were left hungry for more.

One deep thinker, employing a term whose meaning is as elusive as the substance to which she was applying it, presented a paper called “The Semiotics of Jell-O.” The political correctness of the gathering was ensured with a presentation entitled “The Dialectics of Jell-O in Peasant Culture,” while “White Religious Cults: Lime Jell-O and Little Marshmallows” provided that sine qua non of modern academia: a colon in the title.

As Steven Lubar of the museum pointed out, Jell-O is a symbol of modern America: Imamu Amiri Baraka used it as the title of a play attacking white culture, and Jello Biafra was one of the founders (along with the more prosaically named East Bay Ray) of the Dead Kennedys, an anarchist punkrock band from the mid-1980s. In baseball, that most American of games, Charlie Kerfeid of the Houston Astros demanded a signing bonus of thirty-seven boxes of Jell-0 in his 1987 contract. (He lost a lucrative endorsement opportunity when his career promptly went down the drain.)

Yet the symbolism goes beyond nihilist screechers and overweight relief pitchers. Lubar explained how Jell-O, though manufactured from animal skin and bones, is so thoroughly processed that the government does not consider it an animal product. Indeed, most consumers would be hard put to say where it comes from. Jell-O “is completely alienated from its animal roots,” Lubar says. “What better symbol of modern American culture?” Indeed, gelatin is a most protean protein: It can easily be turned into a main dish, a salad, a cake, an academic conference, even a magazine column.

An instructive contrast can be made with another American junk-food icon, Spam. Like Jell-O, Spam begins as animal matter that most people would not recognize as food and ends as a mouth-watering tidbit. In between, both are transmogrified by the alchemy of modern technology, and they emerge renamed, repackaged, and reinvented, not so much food as cultural icon, fetish, the key element in countless folk rituals. Spam adopts the representational paradigm and becomes a sort of meta-meat, more real than the genuine item. Jell-O follows a transformational archetype in which the slimy caterpillar of animal by-products is turned into the beautiful butterfly of a shimmering, transparent, geometrically perfect comestible. This fundamental dichotomy exemplifies the dualistic responses inspired by technology in modern society, and the vital role that Jell-O plays in so many areas of American life—as symbol, as locus of creativity, as inspiration, as dessert—made it the ideal item to discuss on April Fool’s Day.

We hope you enjoyed this essay.

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