How much weight could a Union military wagon carry, assuming a normal
hitch of six horses, and a level, dry dirt road in fair weather ?

Dear hose7,

The sources I found say that U.S. Army wagons during the Civil War
were normally pulled by either four horses or six mules. I did not
find any reference to six horses being the normal number of draught
animals.

Furthermore, the statements on the weight a wagon could carry under
good circumstances vary a bit. But this is not surprising since
horse-drawn wagons are not as standardized as modern motor vehicles.
Also, the effective load of a such wagon was not measures as exactly
as today.


The first statement comes from General William Tecumseh Sherman who
marched through Georgia with an entire army and who thus certainly
knows how much weight his wagons were able to carry. In his memoirs,
General Sherman writes:

"An ordinary army-wagon drawn by six mules may be counted on to carry
three thousand pounds net, equal to the food of a full regiment for
one day." [1]


The second statement can be found in Francis T. Miller's "The
Photographic History of the Civil War":

"The dimensions of the box of these useful vehicles were as follows:
Length (inside), 120 inches; width (inside) 43 inches; height, 22
inches. Such a wagon could carry a load weighing about 2536 pounds, or
1500 rations of hard bread, coffee, sugar and salt. Each wagon was
drawn by a team of four horses or six mules." [2]


And the third statement on the effective load of Civil War wagons
comes from the U.S. Army Center of Military History historian Ted
Ballard:

"An Army wagon, drawn by four horses over good roads, could carry
2,800 pounds. A good six-mule team, in the best season of the year,
could haul 4,000 pounds. In practice, wagons seldom hauled such loads
because of poor roads." [3]


So despite the varying figures, the general image is rather clear:
Under good circumstances, a normal military wagon could carry a load
of about 3000 pounds.

I hope that this answers your question!
Regards,
Scriptor


Sources:

[1] FullBooks.com: The Memoirs of General W. T. Sherman, Vol. II.,
Part 4; by William T. Sherman
http://www.fullbooks.com/The-Memoirs-of-General-W-T-Sherman-Vol-II-x32045.html

[2] Civil War Arms & Equipment Message Board: Mike Bailey in "Re:
Supply Wagons" (30 November 2003)
http://history-sites.com/mb/cw/cwaemb/index.cgi?noframes;read=461

[3] U.S. Army Center of Military History: Staff Ride Guide - Battle of
Ball's Bluff; Logistics, by Ted Ballard
http://www.army.mil/cmh-pg/books/Staff-Rides/ballsbluff/logistics.htm

Search terms used:
"military wagons" pounds "civil war"
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"military wagons" "four horses"
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