English weight measurements

Can anyone please tell me how much a stone is in pounds? You find this referred to in English books and stories, that go something like this “He weighs 10 stone.” I always thought it meant 11 pounds per stone but that does not seem to be enough because when this sentence is used they are referring to a large man (200+pounds) and not 110 pounds.
A second question, how long is a fortnight? Also used in English novels as a measurement of time. Thanks for the help.

Fourteen pound = 1 stone
Fourteen days = fortnight

** http://www.megaconverter.com/mega2/ **

What a cool site, thanks a lot!

BTW, this is really a General Question, so I’m moving the thread so more people can be educated.

your humble TubaDiva

From the most comprehensive site about units:

For what it’s worth, I am 10 stone, and I am actually underweight. So 10 stone does not refer to a large man at all, it is an average to low weight for a male.

I don’t know about all of that, but a friend of mine lives on the East Coast of South Florida and has reported that bales of coke keep occasionally washing ashore from the ocean and now and then, some big plastic wrapped bricks of pot drift up.

He lives near the beach and, for reasons best not disclosed, has been delighted when this ‘treasure’ occasionally washed up at his door step, so to speak. He is, now, real unhappy with his neighbors from a new condo within a half mile of ‘his’ beach because they take early morning walks.

They’ve found some of the rare sea treasure and called the cops, who show up in force, take the goods, scour the area for more and often hide a few plain cloths agents about for a few days to recover anymore that arrives and to arrest anyone ‘salvaging’ it.

He sez that by rights of international salvage of the sea, that which washes up upon his shore belongs to him. The cops say differently.

He’s currently thinking of land mines or something to discourage his ‘neighbors’ from walking ‘his’ section of beach.

Um, CopperTears, I think you might be in the wrong place. Perhaps you meant to post that in the thread Bales of Cocaine?

As to the OP, I feel obligated to point out that stones are not a unit of weight, as pounds are, but a unit of mass, like the kilogram, so strictly speaking, you can’t make a conversion between them without specifying a gravitational field.


I thought the slug was the unit of mass in Imperial system, and that the stone is just a unit of weight, a multiple of pounds, like the quarter and the ton? I belive that the term “stone” to mean 14 lbs. has been around since long before physics made the distinction between mass and weight.


I thought the unit of mass in Imperial system is the “slug,” and that the “stone” is just a unit of weight, a multiple of pounds, like the quarter and the ton?

I believe that the term “stone” to mean 14 lbs. has been around since before physics made the distinction between mass and weight.

yeck - excuse simulpost, please. thought I pushed “preview” - must have been “submit.”

Chronos, are you sure of that? The link I provided above says it is a unit of weight. Can you provide some source?

A kilogram isn’t a unit of mass! It’s a unit of weight! What the hell?


A kilogram is a unit of mass. Something that has a mass of one kg on earth will have the same mass on the moon, and on the space shuttle. If I swing a bat that weighs one kg, with exactly the same speed, and hit you in the face with it, it will do the same damage whether we’re on Earth, in the shuttle, or on the Moon.

Weight, on the other hand, varies with gravitational pull. The same object, with mass of one kg, will have one weight on Earth, another weight on the Moon, and would be weightless in orbit in the space shuttle. The unit of weight in metric (or SI, if you’re picky) is the Newton, defined as a certain mass (1 gram, or 1 kilogram - can’t remember which) under the normal accelaration of Earth gravity - 9.8 m/second/second.

Since few of us ever leave Earth we use the mass measurement to represent weight.

(Hope I got that right - I’m sure if I didn’t, we’ll hear about it.)

We never studied weight when I was at school. Just by a quirk of scheduling through my life, I never managed to end up in a lesson talking about weight. That, coupled with getting imperial measures from my parents and decimal measures from school managed to totally confuse me to the point where, even today, I dunno shit about weight measurements.

So thanks for the correction and explanation.

Consider me officially chastized on the slug/stone issue. I don’t have any cites, so I’ll trust jti and sailor on that one. I’m a physicist, and used to working in the various forms of the metric system (or the Planck system… I’m a theorist :)), so could easily have gotten confused.

Actually, a Newton is one kilogram times one meter per second per second. A dyne is one gram times one centimeter per second per second. The gravitational field at the surface of the Earth is not used in the definition of either, which makes sense when you consider that Newtons/dynes are used for all forces, not just weight.

Chronos - thanks for clarifying the Newton.

I remember now where the “9.8” came from in my thinking: an object with a mass of 1 kg on Earth would have a weight of 9.8 N, right? Since the acceleration would the gravitational pull of the Earth, which is 9.8 m/sec/sec? Or am I hopelessly confused?

Right, F=ma, and the a here is g, so a 1 kg mass on the surface of the Earth has a weight of 9.8 Newtons.