regularly to be the value of a cow or ox, the conclusion must follow that the unit of weight is ultimately derived from the value in gold of a cow.
If we begin in modern times and reflect on the articles which are usually sold by weight, we find at once that the more valuable and less bulky the commodity, the more regularly is it sold and bought by the medium of the scales and weights; furthermore, on enquiry we find that many kinds of goods which are now sold by weight were formerly sold simply by bulk or measure. At the present moment corn is generally sold by weight (though sometimes still by measure), although the nomenclature connected with its buying and selling shows beyond doubt that formerly it was sold entirely by dry measure. The English coomb, the Irish barrel, the bushel and the peck are indubitable evidence. The selling of live cattle by weight has only lately been adopted in some markets in this country; but go back to a more remote period, and you will find that even dead cattle were not sold by weight. Thus we see that it is only in a comparatively late epoch that two of the chief commodities on which human life depends for subsistence have been trafficked in by weight. Nothing now remains but man's clothing, weapons, ornaments, fuel and furniture.
The more primitive the condition of life, the more scanty and rude is the household furniture, and as even in modern times timber is not sold by weight, beyond all doubt the same must hold good in a still stronger degree of a time when wood could be had for the mere trouble of sallying forth with an axe and cutting it. The same argument applies cogently to the question of fuel. For even though coal is now sold by weight, both coal and coke are still sold in some places at least in name by the chaldron, a fact that indicates that it was only when facilities increased for weighing large and bulky commodities that such a practice came into vogue. Similarly, although firewood is now sold by weight on the Continent, beyond all doubt at a previous period it was uniformly sold by bulk, as peat or turf is now sold in Cambridgeshire, in Scotland, and in Ireland.