George Washington weighs his hogs

George Washington is seldom seen as a man of science. But, like others who lived during the Enlightenment, he used scientific ideas, instruments, and experiments to maximize his profits. Despite a meager formal education, Washington was a voracious reader. His extensive library contained some 1,200 titles, 14% of which related to agriculture, and 5% of which related to science, industry, and natural history. And, in his Thanksgiving proclamation of 1789, he spoke of promoting the "increase of science" among Americans and people of other nations.

A metal instrument, stick-like and silver in color. It begins with a sort of wide hook on one end and tapers at the other end. Attached are two hooks that look moveable. There are marking for measurements down the body of the instrument. There is wording etched on the thicker part of the object.

Washington certainly knew that the American colonists, like their friends and relatives abroad, weighed all sorts of things, large and small. Sometimes they used an equal-arm scale in which a weight balances the load. They also used an unequal-arm steelyard (weighing apparatus), a balance with the pivot near one end, rather than in the middle, so a small weight can counterbalance a much heavier load. The Romans knew the instrument as the statera. The English and German "steelyard" is derived from "The Steelyard," the 13th-century German trading post in London.

There is an illustration on a piece of old paper. It is of a harbor. There are ships and a group of people on the dock talking to each other. There is text in a bubble above and the illustration is within some sort of decorative border with laurel leaves accents

In March 1761, soon after settling in at Mount Vernon, Washington ordered four steelyards from his business agent in London. Later correspondence indicates that he used these to track his animals and produce under various conditions. In January 1762, Washington weighed 18 hogs before and after slaughter, to determine the difference between the gross weight of the animals and the net weight of the pork and edible entrails. Other colonists did the same; one colonial newspaper reported a Rhode Island hog that weighed 531 pounds and gave 46 pounds of lard. Another described an 850-pound New Jersey hog as "the largest creature of the kind ever raised in America." Thomas Jefferson, always eager to show that American animals were bigger than those in the Old World, told of a hog that weighed 1,050 pounds "after the blood, bowels, and hair had been taken from him." Jefferson went on to say that "Before he was killed, an attempt was made to weigh him with a pair of steel-yards, graduated to 1,200 lbs. but he weighed more. Yet this hog was probably not within fifty generations of the European stock."

A black hog stands in an enclosure of logs. It has straw all over it.

In 1765, while considering growing wheat rather than tobacco, Washington asked his Alexandria merchants if they would evaluate his crop by weight or volume. He had made some trials, and was unsure whether he should gain or lose by a contract of this kind. Washington also found that weighing was not as reliable as he might wish. "The Wheat from some of my Plantation's by one pair of Steelyards," he noted, "will weigh upwards of 60 lbs., by another pair less than 60 lbs. and from some other places it does not weigh 58 lbs. and better wheat than I now have I do not expect to make during the term of our Contract at least whilst I continue to sow a good deal of Ground." Washington was not alone in finding irregularities of this sort. Each of the colonies had, at an early date, established regulations regarding the use of standard weights and measures, and the regular examination of scales and steelyards.

As a fan of the sport of horse racing, Washington knew that jockeys were weighed before every race, to ensure that each horse carried the same load. And while he was not obsessed with his own weight, he was somewhat interested. In August 1783, as the Revolutionary War was winding down, Washington and 10 of his officers took turns stepping on the scales at West Point. Some years later, while negotiating for the purchase of a horse, Washington noted that the "Size and strength must be equal to my weight, which without the saddle may be estimated at 210 lbs."

Documentary evidence indicates that many scales and steelyards were used in Colonial America, but few authenticated examples are known today. None are in the collections of the National Museum of American History.

Deborah Warner is a curator in the Division of Medicine and Science, who blogs about science and culture. For more, see Michael B. Guenther's Enlightened Pursuits: Science and Civic Culture in Anglo-America, 1730–1760, PhD dissertation, Northwestern University, 2008.