This subdivision develops greatest dexterity and skill, as well as the keenest comprehension of the ways and means of attaining a given end. And this dexterity of operation is more easily carried on than is the fumbling uncertainty of the work of the more primitive type. Care in Applying New Theories. The manual worker's energies are so absorbed in the physical tasks that he is annoyed by any suggestion to change his method. If he were given the position at a desk he would probably be interested in the progressive schemes for betterment of methods of work or management of business. Bearing this state of affairs in mind, it behooves the progressive man to approach the problem of applying his theories in a very careful manner. He must realize that the men in various parts of the work are under stress of every day's requirements that makes it very difficult to intelligently take up any new scheme of procedure. Many an ideal doctrine is a beautiful thing in theory but of little value if its introduction requires an immense but unavailable energy to put it into practise. He must realize that it is the doing of work that counts and that the men who are doing things must not be annoyed. All plans for betterment must conform to the assimilating power of the men and must not cut off their food in time of change. In other words, the new plans should be so matched on to the old methods that the change to the new will not interrupt the production. We have seen that the most efficient way to use man's energies is to allow him to follow habit lines of thought and action, and that the highest efficiency is reached when these habits are habits of concentration of attention and are restricted to the smallest variety of work. Progressive Energy. Progressive energy is so valuable that it needs no praise at this time. We have had its value stated so often that it is actually over-rated in the average mind. Not that it has been over-valued, but that the reiteration has obscured the importance of other qualities. There should be a greater appreciation of the value of energies that are wholly employed in accomplishing results by old means and methods. Progressive energy, when it is kept within certain bounds, is a prime asset of an industrial organization. It is like a wholesome amount of labor to man; it may be drawn upon without loss, and its use actually strengthens its source. But when it is not wisely kept in control it only annoys and interferes with real progress and real accomplishment of results. The only way to get work done is to let the worker move along habit lines. The only way to progress efficiently is to make the new ways and means lead off gradually from those in use. The progressive man who actually directs work along such lines is the most valuable to the world. The one who ignores the "moment of inertia" is a disturber, whether he is a director or a "hewer of wood and carrier of water".