As many as 350,000 people and tens of thousands of covered wagons traveled the Oregon Trail between 1840 and 1870. Countless feet, hooves, and iron-rimmed wheels cut and compacted the ground, leaving long-lasting traces still visible on many western landscapes
Emigrants preferred sturdy farm wagons, roughly half the size of a Conestoga to carry what possessions and supplies would fit. The wagon box was about four feet wide, three feet deep, and 10 to 12 feet long. The covered box sat over two pairs of wheels of different sizes: front wheels about 44 inches in diameter, and rear wheels about 50 inches in diameter.
The narrow iron rims on the wheels, pressed into the earth by the weight of the wagon and its 1600 to 1800 pound load, left a visible legacy across the landscape. In places, faint two-track depressions provide evidence where wagons once rolled across mostly level ground.
Elsewhere are deeper depressions with sloping sides, called swales. Swales are often found on slopes and at the crest of hills, where the oxen dug in their hooves and strained to pull their heavy load.
In wide open places, visitors to the old Oregon Trail might see two, three or more side-by-side lines of depressions, swales, ruts, tracks, or scars. These multiple traces created wherever wagons could spread out across the landscape to
pass other parties or just to escape the choking dust kicked up by those ahead.
Are the depressions seen here ruts or swales.?
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Constructing a Wagon Wheel
The best wheels were made of well-seasoned, durable hardwoods such as white oak or Osage orange. The wooden rim, or "felloes," could be made by steaming or bending wood to form a circle. The wheelwright selected an iron hoop somewhat smaller that the wooden wheel and heated it in a large forge. As it heated, the hoop expanded. The hot band of iron was hammered snugly around the rim and set aside to cool and shrink. The powerful grip of the finished iron tire held the wheel securely together and protected it from rocks, grinding sand, and other hazards of the road.