You learn something new every day...

[kengr]

From a discussion on the Antir mailing list:

Assload, a unit of weight, 276# 4.5OZ., was originally the weight that a donkey could carry safely for 16 miles. [a day's travel] Still used in South America by coffee-growers, it was replaced in Europe about the 1500's when horses replaced jackasses as dray animals.

(later comment by poster above)

Check your copy of "From the Obscure to the Obsolete" compiled by William Frankens, Published 1986 by Harcourt, Brace, Jovanovich. Chapter 6 deals with unusual units of measurement.

Comments

[mhw.livejournal.com]

Hm. Seems weirdly precise to me. Nearly 300lb, but measured to the half-ounce?

[kengr]

My guess is that it was originall measured using some weight units outher than ounces & pounds.

I think someone in the discussion said something about it being 2.5 hundredweights (which were something like 112 pounds and change).