Comments on: First Emperor showed the way – 2000 years ago

By: Daniel Jackson

Daniel Jackson — Sat, 19 Apr 2008 13:49:11 +0000

Martin,

In some people’s view, natural means human scale. In the absence of devices to measure, the foot becomes a unit of length, as does the hand, elbow and thumb.

The pound, I believe, developed from what the average person could hold in their hand. If a trader in the ancient days did not have a scale, and someone wanted two pounds of something, that meant two of whatever they could grab with their hands.

The kilogram is not considered natural because it isn’t something you can easily grab at one time with your hand.

[The absurdity of this argument is exposed in two previous articles on MetricViews. See

http://www.metricviews.org.uk/2008/01/01/is_imperial_natural/

and

http://www.metricviews.org.uk/2007/10/28/imperial-units-natural/

Furthermore, both the kilogram and the pound are measures of mass (or, for most practical purposes, weight) - not of size. Whether you can hold them in your hand depends on their density. - Editor]

By: Martin W

Martin W — Thu, 17 Apr 2008 11:59:50 +0000

The 500g Chinese jin, or catty, was not ‘introduced’ to replace something that was ‘missing’ from SI. It was part of a redefinition of all the old Chinese measurements in terms of rational metric values.

Warwick, I assume from your comment that you regard the kilogram as being not ‘natural’, but that the 454g avoirdupois pound and 500g Chinese jin somehow are. What are the minimum and maximum values that you use to define whether a measurement unit is ‘natural’? Would the old 605g Chinese jin fall into this definition too?

Are lines, inches, hands, links, feet, yards, rods, chains, furlongs, miles and leagues ALL ‘natural’ units?

By: Warwick Cairns

Warwick Cairns — Wed, 16 Apr 2008 22:16:25 +0000

The litre does seem to be around the right size for a ‘natural’ unit. Interestingly it was never part of the original metric system – the ‘correct’ measure was the cubic metre or Stere. The litre, more or less equal to the old British (and current American) quart of 32 ounces, was the old French Pinte reintroduced as the Litre when Napoleon abolished the metric system.

On the subject of Chinese measures, it’s interesting to note that the Chinese have introduced a half-kilogramme ‘metric pound’ or Gongjin – again, a ‘natural’, convenient size missing in the strict SI version.

If all this sounds geeky and obscure, that’s not the half (or 0.5) of it: in fact I’ve written a whole book on the subject, About the Size of It, published by Macmillan. You can read excerpts on my website.

By: Phil H

Phil H — Mon, 14 Apr 2008 22:25:02 +0000

It is significant that the imperial “system” as defined in 1824 is superior to the mish-mash of units we ended up with in the latter half of the 20th century. There was at least an integral relationship between linear and volumetric or so-called liquid measure, namely that a cubic foot was 50 pints or 1000 fluid ounces.
Since the 1963 weights and measures act the pint is defined as (exactly) 568.261485 ml and the inch exactly 25.4 mm which makes the cubic foot 49.830663065261232687624430503151 … pints.
One would have hoped that the disregard shown for any coherence in imperial measures was at least in deference to the far more logical and coherent metric system that would replace it. Since this is has not been done properly we have been left with the worst of all possible worlds.