It is, indeed, evident from observation, as it must be from theory, that whatever be the circumstances which produce the differences of wages in different occupations, and although they frequently vary in relation to each other, producing, as between time and time, and place and place, greater or less relative differences, yet the rate of wages in one occupation is always dependent on the rate in another, and so on, down, until the lowest and widest stratum of wages is reached, in occupations where the demand is more nearly uniform and in which there is the greatest freedom to engage. For, although barriers of greater or less difficulty may exist, the amount of labor which can be determined to any particular pursuit is nowhere absolutely fixed. All mechanics could act as laborers, and many laborers could readily become mechanics; all storekeepers could act as shopmen, and many shopmen could easily become storekeepers; many farmers would, upon inducement, become hunters or miners, fishermen or sailors, and many hunters, miners, fishermen, and sailors know enough of farming to turn their hands to it on demand. In each occupation there are men who unite it with others, or who alternate between occupations, while the young men who are constantly coming in to fill up the ranks of labor are drawn in the direction of the strongest inducements and least resistances. And further than this, all the gradations of wages shade into each other by imperceptible degrees, instead of being separated by clearly defined gulfs. The wages, even of the poorer paid mechanics, are generally higher than the wages of simple laborers, but there are always some mechanics who do not, on the whole, make as much as some laborers; the best paid lawyers receive much higher wages than the best paid clerks, but the best paid clerks make more than some lawyers, and in fact the worst paid clerks make more than the worst paid lawyers. Thus, on the verge of each occupation, stand those to whom the inducements between one occupation and another are so nicely balanced that the slightest change is sufficient to determine their labor in one direction or another. Thus, any increase or decrease in the demand for labor of a certain kind cannot, except temporarily, raise wages in that occupation above, nor depress them below, the relative level with wages in other occupations, which is determined by the circumstances previously adverted to, such as relative agreeableness or continuity of employment, etc. Even, as experience shows, where artificial barriers are imposed to this interaction, such as limiting laws, guild regulations, the establishment of caste, etc., they may interfere with, but cannot prevent, the maintenance of this equilibrium. They operate only as dams, which pile up the water of a stream above its natural level, but cannot prevent its overflow.