第107章

In modern Europe, too, 'the strength of the effective desire of accumulation, seems to have been always greater, than in any other part of the old world.

This circumstance has much facilitated the passage into it, of the several arts, and balancing the higher rates of wages, and more stubborn materials, has rendered the formation of very many instruments there practicable, which the weaker accumulative principle of the Asiatics, or Africans, would have left unattempted.

It is worth while to remark, that there is a considerable analogy in this particular, between the different conditions of society in that continent and Asia then, and what exists between them now, in Europe and North America.

The general wages of labor seem always to have been higher in Europe, than in Asia, in the same way as the wages of labor in North America, are now higher than in Europe.The same process, too, that carried the arts to Europe, seems now aiding their passage across the Atlantic.As flame often sets against the wind for that it is fed by it, so invention seems to hold its course against opposing obstacles, for these obstacles excite its powers and minister materials to their action.

The progress of the knowledge of the natures and qualities of particular substances, gradually introduced a knowledge of the properties and natures of substances in general.Men first see in the concrete, afterwards in the abstract.Thus, the discovery of the several mechanical powers, and the knowledge acquired of the nature of each, led in time to the general principles of mechanics.A knowledge of the mathematical properties of substances, as in land-measuring, and in the regular figures of architecture, led to a perception of the general properties of figure, or of space as an affection of matter, and, at last, to the doctrine of pure space and motion.

In the ancient world, science, as rounded on a generalization of the experiences of art, was little prosecuted.It is only in modern times, that the science of experience has come to form an element of importance, in the general advance of invention.

It is clearly on the antecedent progress of art, that the foundation of the hopes of Bacon, for the future progress of science, rested.His philosophy may be tidy described, as a plan to reduce to method the chance processes that had been going on before, by which men, as we have seen, happening on one discovery after another, grope their way, as he expresses it, slowly, and in the dark, to fresh knowledge and power.The progress of the philosophy to which he has given his name, as well as that of the science of mathematics, have unquestionably discovered to us many general truths, and theorems of art, and form therefore a new element influencing its progress.The great moving powers will, however, still, I apprehend, be found to proceed from the principles, the action of which we are now to attempt farther to trace through particular instances.

Men must have been very early led to the use of some of the farinaceous plants, and other vegetable matters, which, before they are fit for food, require to be reduced to small fragments.To effect this, they must either have rubbed them, or beat them, between some two substances.If stone were the material, they would rather prefer rubbing them, from the liability of that substance to break, and from its weight.It is thus that the rude tribes of southern Africa, to this day, lay their corn on one fiat stone, and grind it by the help of another.An improvement on this instrument, is to have the lower stone a little hollowed, and perhaps marked with transverse notches.In one form or other, this is a very general and ancient instrument, and, it may be observed, is probably the first machine in which a circular motion was introduced.

If wood be the material, then, to produce any effect, the substance to be comminuted must be laid on one piece, and another be struck against it.But, thus, a large portion of the matter operated on would fly off, and be lost.The most natural mode of preventing this, is, to hollow out the lower piece.Tho Indians of North America make an instrument of this sort, very easily, by taking a portion of the trunk of a tree of hard wood, setting it upright, and burning and scraping out a hole in the upper end.

They have then a large mortar, to which adjusting a wooden pestle, they produce the implement with which they pound all their corn.Such an instrument seems, like its fellow of stone, to have been in very general use, at one time or other, in most parts of the world.(71)Tribes having learnt the use of such an instrument, on substances most easily comminuted, would be urged on to essay its powers on more cohesive matters.They might succeed in the attempt, at first, by simply increasing the size of the implement, and searching out the hardest and heaviest woods to construct it of, but, even these improvements would at length bo insufficient for the enterprizes to which their confidence in their powers, or their necessities, might excite them.To overcome these increasing difficulties, it would require no great stretch of the inventive faculty, to hit on the expedient, of placing a firm transverse bar, with a hole in it, for the passage of the handle of the pestle, across the top of the mortar, from side to side.Such a change in its construction, seems accordingly, to have been very generally effected.Simple as it is, it contained the germ of very many subsequent improvements.The force employed, acting thus not directly, but through the intervention of a fulcrum may be so applied as to give either increased velocity, or increased power, and the regulated movement introduced renders mere power almost all that is necessary.The size of the mortar, and weight of the pestle, might, therefore, be increased indefinitely, and the instrument might be put in motion by men, or by cattle.