The origin of the slug of mass (lbf�s�/ft = 14.594 kg), also known as the
"gee-pound," and seemingly much loved by wombatiferious aerospace folks,
has an obscure origin. It belongs to the so-called "British Gravitational
system," but is not mentioned in the unabridged Oxford English Dictionary.
However, it's in all my American dictionaries, but without an etymology. In
the 19th century, the word "slug" was used on both sides of the Atlantic for
a nugget of gold or other metal of around 15 to 20 lb, so maybe that's the
origin. As Joe notes, its technical use seems to be quite recent. Then there
is the slinch of mass (slug-inch = lbf�s�/in = 12 slugs = 175.13 kg),
invented by NASA in the 1960s. Of course, every American understands these
good ol' units perfectly, while finding the kilogram impossibly
inscrutable.
> -----Original Message-----
> From: Joseph B. Reid
>
> Engineers
> have habitually used [the pound of force] as a unit of weight, and when
that got the
> aeronautical engineers into trouble, they invented the slug which has no
> legal sanction behind it. The slug as a unit of mass does not appear in
> the 1970 edition of the Shorter Oxford Dictionary of the English Language,
>
> Physicists, with a better understanding of Newton, retained the pound as a
> unit of mass, and invented the poundal as the corresponding unit of force.
> The Oxford dictioary dates the poundal from 1879.
>
> Joseph B. Reid
> 17 Glebe Road West
> Toronto M5P 1C8 Tel. 416 486-6071
>
>
