ONE:Macaulay has spoken as if the Platonic philosophy was totally unrelated to the material wants of men. This, however, is a mistake. It is true that, in the Republic, science is not regarded as an instrument for heaping up fresh luxuries, or for curing the diseases which luxury breeds; but only because its purpose is held to be the discovery of those conditions under which a healthy, happy, and virtuous race can best be reared. The art of the true statesman is to weave the web of life with perfect skill, to bring together those couples from whose union the noblest progeny shall issue; and it is only by mastering the laws of the physical universe that this art can be acquired. Plato knew no natural laws but those of mathematics and astronomy; consequently, he set far too much store on the times and seasons at which bride and bridegroom were to meet, and on the numerical ratios by which they were supposed to be determined. He even tells243 us about a mysterious formula for discovering the nuptial number, by which the ingenuity of commentators has been considerably exercised. The true laws by which marriage should be regulated among a civilised people have remained wrapped in still more impenetrable darkness. Whatever may be the best solution, it can hardly fail to differ in many respects from our present customs. It cannot be right that the most important act in the life of a human being should be determined by social ambition, by avarice, by vanity, by pique, or by accidentin a word, by the most contemptible impulses of which human nature is susceptible; nor is it to be expected that sexual selection will always necessitate the employment of insincerity, adulation, and bribery by one of the parties concerned, while fostering in the other credulity, egoism, jealousy, capriciousness, and petty tyrannythe very qualities which a wise training would have for its object to root out.145At Riemst, the soldier took, or rather pummelled me into a large farm-house, and soon I faced the bigwigs, who had made themselves as comfortable as possible in a large room. Several pictures and engravings lay on the ground in pieces, whilst numerous full and empty wine-bottles indicated that they had abundantly worshipped at the shrine of Bacchus, and intended to go on with the cult. The higher officers and the subalterns seemed to be frantically busy; at least they had violent discussions with many gesticulations over a map. The soldier reported that he had brought me here by order of Lieutenant SuchI did not catch the nameand then it began:
TWO:A gravity wheel must have a diameter equal to the fall of water, or, to use the technical name, the height of the head. The speed at the periphery of the wheel cannot well exceed sixteen feet per second without losing a part of the effect by the wheel anticipating or overrunning the water. This, from the large diameter of the wheels, produces a very slow axial speed, and a train of multiplying gearing becomes necessary in order to reach the speed required in most operations where power is applied. This train of gearing, besides being liable to wear [38]and accident, and costing usually a large amount as an investment, consumes a considerable part of the power by frictional resistance, especially when such gearing consists of tooth wheels. Gravity wheels, from their large size and their necessarily exposed situation, are subject to be frozen up in cold climates; and as the parts are liable to be first wet and then dry, or warm and cold by exposure to the air and the water alternately, the tendency to corrosion if constructed of iron, or to decay if of wood, is much greater than in submerged wheels. Gravity wheels, to realise the highest measure of effect from the water, require a diameter so great that they must drag in the water at the bottom or delivering side, and are for this reason especially affected by back-water, to which all wheels are more or less liable from the reflux of tides or by freshets. These disadvantages are among the most notable pertaining to gravity wheels, and have, with other reasonssuch as the inconvenience of construction, greater cost, and so ondriven such wheels out of use by the force of circumstances, rather than by actual tests or theoretical deductions.
