It would appear, then, that here we have a combination of units of weight and units of capacity. The higher gold and silver unit, the _nên_, is simply the tenfold of the lower unit, the _tael_ or ounce, while the _catty_, which is never employed in China in estimating gold or silver, but is a genuine commercial unit, was probably originally some natural unit of capacity. We saw strong evidence of this in Cambodia, where the name for this weight is _neal_ or cocoanut, and we have just found the cocoanut as the chief unit of dry measure amongst the Malays of the Indian Seas. It was probably found that 16 times the _tael_ or ounce came nearer to the weight of the contents of a cocoanut or bamboo joint (whatever kind of matter they may have weighed in it for this purpose, whether rice, or water), than the original 10 ounces, which formed the _bar_, the highest genuine weight unit. Sixteen was likewise a convenient number, its factors being numerous, and it could be divided in four portions, each of which contained four other units. It will presently be a question as to whether similar influences have not produced our pound avoirdupois, with its 16 sub-multiples. M. Moura found a difficulty regarding the Cambodian _neal_ or cocoanut _catty_; because a _neal_ of rice only weighs half the weight, at which the _neal_ is rated as a weight. But we saw in Java that the _chapa_ or cocoanut measure is estimated at 2½ pounds avoirdupois. It is then not improbable that some liquid or substance far heavier than rice was used to fill the cocoanut, when the value of its contents was being ascertained by weighing so as to serve as a general unit. The same variation in weight, owing to the different nature of its contents, has, as mentioned before, given rise in Ireland to _barrels_ of various weights. Thus a _barrel_ of wheat contains 20 stone avoirdupois, a _barrel_ of potatoes 24 stone, a _barrel_ of barley 16 stone, and a _barrel_ of oats 14 stone. This diversity simply arose from comparative lightness or heaviness of the different commodities which were measured by one and the same unit of capacity: the barrel itself, having been fixed by a process of measurement, similar to that by which the milk-pan was regulated among the Welsh, and the pannier among the natives of Laos. The principle by which higher units of capacity or weight are formed is likewise well illustrated by the instance given above of the _cartload_ of rice, which is simply regarded as the multiple of the pannier or bag, which forms the smaller unit for rice. The size of the _cartload_ would be conditioned by the size of the cart usually employed, which in turn would depend on a variety of other things, such as the nature of the country, or its roads, or the kind of animals employed for draught. The vagueness in amount of the _koyan_ or multiple of the _picul_ noticed by Crawfurd, may thus meet with a reasonable explanation.