The story goes like this. An eighth of a mile therefore became known as a furrow-long or furlong; a furlong is a nearly forgotten term for distance, except at horse racing tracks where it remains in common use. The usual practice after plowing a furlong was to then turn the team around on a "land" and plow the other direction.
Lands were laid out so the farmer would be able to finish a land every 10 rounds with a 10 inch plowshare about One could imagine that perhaps farmers used a pole or rod that was By starting early in the morning, two lands could be finished before noon with a good yoke of oxen. At noon, the farmer stopped for his noon meal and to feed, water, and rest his animals. After the noon break, another two lands could be finished before quitting time.
Four lands, or forty rounds 80 furrows measured The area plowed was therefore 43, square feet and became the standard unit of land area we call an acre. By the way, a farmer who plowed 80 furrows an eighth of a mile long would have walked ten miles while wrestling with the hand guided walking plow. The Scottish acre is 1. Unit of length and area used in France, Louisiana and Canada. As a unit of length, an arpent is approximately The square arpent is a unit of area, approximately.
Chains equal to two poles one half the standard length are found in Virginia. The name comes from the heavy metal chain of links that was used by surveyors to measure property bounds. Unit of length equal to 66 feet, or four poles. This unit was apparently defined as one tenth of a furlong, a common unit of length in the old days. The mile was redefined from 5, feet to 5, feet in order to be an even multiple of furlongs.
A mile is 80 chains. Are they as if the hill were cut off and the land was level? Or up one side of the hill and down the other as if it were covered with a blanket and then the size of the blanket was measured? Answer: It's as if the hill were cut off and the land was level. To quote from an old authoritative surveying text, by two professors at MIT:. Horizontal Lines. As a matter of convenience, measurements are sometimes taken on slopes, but the horizontal projection is afterward computed.
The distance between two points as shown on a map then is always this horizontal projection. Charles B. Breed and George L. The Principles and Practice of Surveying , Vol 1. The modern method of observing with the circle level provided with a telescope having a vertical motion enables one to ascertain at once the horizontal angle between points of different elevations. Then we project all vertices upon the surface of an ellipsoid which differs the least possible from the mathematical shape of the earth and bind these points with lines upon this surface.
After deducting equally from each angle the computed spherical excess, the computations are carried forward in accordance with the established principles of plane trigonometry. Howard Gore. Boston: Houghton Mifflin, Pages Download a printable, letter-size chart as seen at the right to convert between acres and hectares visually. The calculator below gives the number of acres in a rectangular field.
Or, enter the acreage and a width, and the length will be calculated. Choose the unit in which you will measure lengths: feet yards meters rods miles. Sometimes when sowing seed or applying fertilizer to hilly ground, it is useful to know the actual surface area, as if the land were flat.
The calculator below makes a rough estimate based on the slope of the ground. Acreage : acres. The acre was originally the amount of land that could be plowed in a single day with oxen , or actually, what could be done by midday, since refueling took all afternoon the oxen had to be put out to pasture.
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