Several points of great importance are to be noticed in the foregoing statements. Firstly, that whilst for foreign trade with the Chinese they employ the Chinese weight, which we know always by its Malay name of _picul_, a well-defined weight standard of 133⅓ lbs. avoirdupois, they had evidently a native unit of weight, their own _picul_, which simply means and actually was as much as a man can carry on his back, and which, as we saw, rarely exceeds 80 lbs. avoirdupois. This seems to give us an insight into the manner in which the most primitive highest weight unit is arrived at. A man’s load is one of those natural standards which will vary according to race and climate, and the conditions under which the load has to be borne. Thus, the average weight of the load borne by a dock porter who has to endure the strain for only some few yards, will of course be far higher than that carried by the porters of travellers in Central Africa, where the load has to be borne day after day on a march of several hundred, or a thousand miles. Thus in the case of the Madis, a pure negro tribe, the average load seems to be about 50 pounds, which they can carry “20 miles a day for eight or ten consecutive days without shewing any signs of distress[228].” The Chinese, the superiors in science of all Eastern Asia, have carefully adjusted this “_load_,” and it makes, as we have seen above, their highest weight unit. Its particular amount is probably due to the fact that, having carefully fixed the weight of the smaller units, the candarin, the mace, the _liung_ or _tael_, and the _catty_, their pound, they simply took the hundredfold of the _chang_ or _catty_ as the standard for their highest unit, and thus that which at an earlier stage was just as vague and fluctuating as the _picul_, or back-loads in use still among the less-advanced peoples of the Indian Archipelago, became a fixed scientific unit. Secondly, we must notice that the Malays have not followed the Chinese in the subdivisions of the _catty_. For whilst in China 16 _taels_ or ounces go to the catty, the Malays follow more strictly the decimal system, and make their catty simply the tenfold of the _tael_ or ounce. This same method of division we found already in Annam, and not only in Annam but also in Cambodia and Laos we found the silver _nên_ or bar, invariably consisting of ten such parts, corresponding in weight to the Chinese _tael_, sixteen of which go to the catty.