§ 7. Agencies for altering stuff or material. Man can not create a single atom of matter. He must work with the materials which nature puts at his command.3 In what sense, then, may we say that man can change the stuff or material of which things are composed ? There are many chemical and biological processes instituted by man which bring about changes in the chemical content and material composition. One of the most important ways in which man makes alterations of this kind is in tilling the soil. The farmer plants the seed in carefully prepared ground in such a way that the proper conditions of air, light, and water permit plant-growth, and cause the regrouping of the chemical elements of the soil into new forms of organic matter. The first rude cultivation of the soil was a step beyond the achievements of any animal. It meant the purposeful increase of the kinds of stuff man desired, by a method very different from the gathering of honey by the bee or the hoarding of nuts by the squirrel.

3 Refer to ch. 3, sec. 1, on Inherent physical nature of things.

Another important way of making changes in the composition of materials is by breeding and raising domestic animals. Animal growth transforms the food elements into new substances, such as wool, hides, furs, feathers, fat, eggs, bristles, etc. Still another way is seen in the chemical processes of manufacturing, such as iron smelting and other metallurgical operations, tanning, the dyeing of clothes, and the preparation of food as in baking, fermenting, distilling, etc.

To make possible all the changes which man desires in the composition of things, an enormous equipment of indirect agents must be permanently maintained - such things as cultivated soil, agricultural implements, seeds, animals, fertilizers, chemical agents, vats, caldrons, furnaces, fuel, etc., etc. All these things are of value to man (among other reasons) because of the changes in stuff or material which they help to bring about.

§ 8. Agencies for changing the form of things. The alterations in the materials of which things are composed that do not involve chemical or organic changes may be classed under the heading of changes of form. It is probably best to class here most of the operations in the so-called extractive industries (other than agriculture). Such are the processes of mining or of quarrying in which organic or mineral materials are blasted, dug, or broken into sizes and shapes convenient for removal; and the process of forestry in which timber is cut and prepared to be taken from its place of growth. There is always, however, a considerable amount of place change involved in these processes. Here, certainly, with form-change may be classed the grouping or arranging of things in new physical relationships - such mechanical operations, for example, as cutting, sawing, splitting, grinding, putting together with nails, screws, or glue, roughening, polishing, etc., etc. Changes of this sort - as well as chemical changes - play a large part likewise in the processes of agriculture; for example, in plowing, in hoeing, in cutting grain, in trimming trees, and in shearing sheep. Some of the most familiar and typical instances are found in manufacturing establishments, such as sawmills, planing mills, and factories for shaping wood, iron, leather, clay, and other materials. A large part of the preparation of food involves changes of this kind. The performance of all these operations involves, of course, an enormous equipment of indirect agents - in the home, on the farm, in shop and factory. This includes a large part of the stock of tools and machines, tho many of these are used also in effecting changes in stuff, place, and time.

§ 9. Natural members as agents in effecting changes of form. In the course of evolution animals have developed special organs which enable them to bring about changes in the form of things. The foot, the paw, and the tail, subserving largely the purposes of locomotion, are also of use in making physical changes in the environment. Animals have teeth to crush and cut; claws and nails to scratch and tear, pick and bore; hoofs to strike; horns and tusks to pierce, push, and crush. The sword of the swordfish, the proboscis of the mosquito, and the trunk of the elephant are highly specialized organs for acting upon the environment.

Compared with many animals man is in many respects poorly equipped with such natural weapons and agents. The human hand, however, is perhaps on the whole the most adaptable and effective agent which nature has produced.

§ 10. The use of tools by man. Man is the tool-using animal. The intelligence which directs and guides the hand has enabled man to contrive external agents of the most marvelous ingenuity and power. The first tools, as is shown in every anthropological museum, were but natural objects taken to increase the efficiency of man's body in acting upon the outer material world. These first inventions were evidently hit upon almost by chance, and yet probably not without some dim perception of the fitness of indirect means to attain the ends desired. The stone held in the hand multiplies many fold the force of the blow. The chance piece of sharp or jagged flint is vastly more effective than nails or claws in cutting and tearing. Boulders and stones shaped by nature or very slightly modified were the first rude hammers, axes, and knives. The log used as a roller under a heavy load seems to have been the earliest form of the wheel.

Even such primitive appliances greatly extended man's control over the world about him. With the stone ax thrown from the hand he could kill animals in full flight. The spear enabled him at a safer distance to kill some of his most dangerous enemies. The bow and arrow and the use of fire must have made his supremacy far more secure. For thousands of years, however, the first tools changed but slowly. It was difficult to get beyond the simple, natural implements picked up by chance.

§ 11. The gradual improvement of indirect agents. In the course of centuries tools and weapons gradually became more efficient. Flint and stone forms were copied in bronze and in iron. Their number and variety steadily increased. Better and more numerous hammers, axes, spears, bows, and arrows were made. Domestic animals were increasingly utilized for food, clothing, and for the carrying of burdens. As a rule the stocks of goods with indirect uses accumulated by primitive man differed little in physical character from his goods with direct uses. Many of them, indeed, were things having alternative uses, some direct, others indirect. It is likely that horses were used to carry men on their backs long before they were taught to carry other burdens or to draw heavy loads. The weapons of the chase were as much a means of sport as a means of securing food, and such things as clothing, tools, and weapons, and even horses and slaves, seem to have been regarded by primitive man as agents to use directly for enjoyment rather than as merely indirect means of getting other goods. This attitude of mind probably helps explain the custom of burying such things with the owner in his grave - a practice which greatly hindered progress, as it kept the primitive community in poverty. Where such customs were not in vogue man's control over his environment developed through the gradual increase in his instrumental equipment from generation to generation.

§ 12. Tools and machines. It is not easy, perhaps not important, to draw a sharp line of distinction between the machine and the tool. Tools are portions of matter, such as bone, wood, iron, which man guides and directs in applying his energy to things. The simple hoe held in the hand and moved by man's own strength was attached to the beast of burden and became a plow or harrow, still guided by man. A machine may be defined as a mechanical device by which power is applied in an automatically repeated manner, to change the place or form of things. A machine may be moved by the foot, but the hand is the great tool-using member. A simple, single piece, that can be taken into the hand, as a spade, a hammer, a knife, is clearly a tool; a combination of parts, such as wheels, levers, pulleys, etc., moving upon each other, is clearly a machine. It is doubtful whether the plow should be called a machine. The simplest machine is but a slight adaptation of the tool, by which power may be applied in an automatically repeated manner. The drag develops into the cart, a simple machine. The spinning stick, a tool used in ancient times, developed into the Saxon spinning-wheel of the sixteenth century, the form used when America was colonized. "Wind and water were made to turn wheels to supply the power for moving tools, to grind the corn, and to lift the hammer too heavy for man's strength. The use of power derived from nature, while not the most essential mark of machines, is the most characteristic feature of their modern development. Hand machines, such as the handpress and typewriter, have had important industrial results, but it is the use of power that has led to the results of greatest significance in recent times.

§ 13. The age of machinery. Inventions, new machines, and new processes, tho not frequent, were not unknown in the Middle Ages; but no one class of machines took possession of whole fields of industry. The great industrial changes in the Middle Ages generally grew out of political changes, or of changes of routes of trade whereby large industries were disturbed, or of changes in the use of land through new methods and the bringing into use of land in other places. The industrial changes in England at the end of the eighteenth century, and a little more tardily throughout western Europe and the United States, on the contrary, were due mainly to great mechanical inventions. The age of machinery is, therefore, said to begin with the eighteenth century. The development of the textile machines for cotton and wool spinning and weaving marks the beginning of the movement. Here for the first time were inventions in such numbers, of such a nature, and under such conditions that they were rapidly and widely applied, affecting the lives of a great number of workers. The steam engine at the same time opened up the long line of mechanical inventions by which wood and iron are shaped and wrought, and the iron industry underwent notable developments. Since that time have taken place in all western countries that rapid expansion in the use of machines and those notable changes in industrial organization which distinguish our era from all others.