There is the alternate increase and decrease of muscular strain implied bythe ascents and descents to the higher and lower notes -- ascents and descentscomposed of smaller waves, breaking the rises and falls of the larger ones,in a mode peculiar to each melody. And then we have, further, the alternationsof piano and forte passages. That these several kinds of rhythm, characterizingaesthetic expression, are not, in the common sense of the word, artificial,but are intenser forms of an undulatory movement habitually generated byfeeling in its bodily discharge, is shown by the fact that they are all traceablein ordinary speech, which in every sentence has its primary and secondaryemphases, and its cadence containing a chief rise and fall complicated withsubordinate rises and falls. Still longer undulations may be observed byevery one in himself and in others, on occasions of extreme pleasure or extremepain. During hours in which bodily pain never actually ceases, it has itsvariations of intensity -- fits or paroxysms; and then after these intervalsof suffering there usually come intervals of comparative ease. Moral painhas the like smaller and larger waves. One possessed by intense grief doesnot utter continuous moans, or shed tears with an equable rapidity; but thesesigns of passion come in recurring bursts. Then after a time during whichsuch stronger and weaker waves of emotion alternate, there comes a calm --a time of comparative deadness; after which dull sorrow rises afresh intoacute anguish, with its series of paroxysms. Similarly great delight, asshown by children who display it without control, undergoes variations inintensity: there are fits of laughter and dancing about, separated by pausesin which smiles, and other slight manifestations of pleasure, suffice todischarge the lessened excitement. Nor are there wanting evidences of mentalundulations greater in length than any of these. We continually hear of moodswhich recur at intervals. Many persons have their days of vivacity and daysof depression. Others have periods of industry following periods of idleness;and times at which particular subjects or tastes are cultivated with zeal,alterating with times at which they are neglected. Respecting which slowoscillations the only qualification to be made is, that being affected bynumerous influences they are irregular. §87. In nomadic societies the changes of place, determined by exhaustionor failure of the supply of food, are periodic; and in many cases recur withthe seasons. Each tribe that has become partially fixed in its locality,goes on increasing until, under pressure of hunger, there results migrationof some part of it -- a process repeated at intervals. From such excessesof population, and such waves of migration, come conflicts with other tribes;which are also increasing and tending to diffuse themselves. Their antagonismsresult not in a uniform motion, but in an intermittent one. War, exhaustion,recoil-peace, prosperity, and renewed aggression: -- see here the alterationas occurring among both savage and civilized peoples. And irregular as isthis rhythm, it is not more so than the different sizes of the societies,and the involved causes of variation in their strengths, would lead us toanticipate.
Passing from external to internal social changes, we meet this backwardand forward movement under many forms. In commercial currents it is especiallyconspicuous. Exchange during early times is carried on mainly at fairs, heldat long intervals. The flux and reflux of people and commodities which eachof these exhibits, becomes more frequent as national development brings greatersocial activity. The rapid rhythm of weekly markets begins to supersede theslow rhythm of fairs. And eventually exchange becomes at some places so active,as to bring about daily meetings of buyers and sellers -- a daily wave ofaccumulation and distribution of cotton, or corn, or capital. In productionand consumption there are undulations almost equally obvious. Supply anddemand are never completely adjusted, but each, from time to time in excess,leads presently to excess of the other. Farmers whO have one season grownwheat abundantly, are disgusted with the consequent low price, and next season,sowing a much smaller quantity, bring to market a deficient crop; whencefollows a converse effect. Consumption undergoes parallel undulations thatneed not be specified. The balancing of supplies between different districts,too, entails oscillations. A place at which some necessary of life is scarce,becomes a place to which currents of it are set up from other places whereit is relatively abundant; and these currents lead to a wave of accumulationwhere they meet -- a glut: whence follows a recoil -- a partial return ofthe currents. But the undulatory character of these actions is best seenin the rises and falls of prices. These, when tabulated and reduced to diagrams,show us in the clearest manner how commercial movements are compounded ofoscillations of various magnitudes. The price of consols or the price ofwheat, as thus represented, is seen to undergo vast ascents and descentshaving highest and lowest points that are reached only in the course of years.
