Eclogue VI. — On the Nature of the Pound or Balance

Whoso you are who wonder that the vast heavenly bodies still endure, hung round about the lofty circle of the firmament, and that no decay creeps in upon their mighty mass, hearken, that you may wonder yet the more. First-beginnings of utmost fineness and which baffle our sight, are in these great bodies: they hold close together, closely linked in a group of tiny atoms; but in these tiny atoms is a solid particle which cannot be parted. Hence comes it that their strength and power endure, and that these motions are not overcome by any lapse of time. We may compare things human with divine.

In the same way the pound is a solid whole, for it consists of twelve equal parts, and in these equal parts, small though they are, one virtue always abides. For if aught is subtracted from their sum, the total is impaired, the parts are thrown out of place and fall because the frame is ruined. As, if we were to wrench out from an arch the keystone upon which all the voussoirs bear, the rest will follow suit and come to the ground, their general downfall caused by the topmost stone; even so is it with the pound. If one ounce is wanting, it will no longer be a pound, but being short in weight will be called deunx (eleven-twelfths). The dextans (five-sixths), too, does not retain that name if a sextans (one-sixth) be taken from it, and the dodrans (three-quarters) will be left without the author of its being if we subtract the quadrans (one-fourth). So, too, the bessis (two-thirds) cannot endure once the triens (one-third) is torn from it. Take away one scruple, and you will have no quincunx (five-twelfths) left you. And how can the semis (one-half) be a half if the fractions of the pound thus waste away? And of what pound will the septunx (seven-twelfths) stand for seven parts? That is a pound, then, which is impaired in no single part. Weight and number, character, tasks, and waters — all have a libra: there is no form of regulation which you may not mark with this name. There is a libra of the earth, which hangs in mid-air, and a libra of their own controls the paths of the Sun and Moon. Libra measures out equal hours of day and night, a libra curbs the Caledonian tides unaided by the shore: do thou also remain the sure libra of my character.