_Regularity and Slowness of Movements caused by Changes in the Amounts of Labor and Capital._--The important fact about the movements thus far traced is that they are steady and slow. They do not often call for taking out of one part of the system mature men who have been trained to work there. They are movements of _labor_ which do not, in the main, involve any considerable moving of _laborers_ from group to group. The sons of the men in the subgroup A do not all succeed to their fathers' occupations, but many of them enter _A'_, _A''_, and _A'''_, so that labor moves from the lowest subgroup to higher ones. Such a transfer of labor entails few hardships for any one, and in general it is to be said that all the movements of labor and capital which are occasioned by quantitative changes in the supply of these agents are of this comparatively painless and frictionless kind. About changes caused by new methods of production there is a different story to tell. The transformation of the world does not go on without some disquieting results, however inspiring is the remote outlook which they afford. The irregularity of the general movement, the fact that it goes by forward impulses followed by partial halts, is a further serious fact. Hard times present their grave problems, and we need to know whether it is necessary that dynamics--the natural and forward movement of the industrial system--should produce them. This problem is for later consideration. _Movements caused by Changes in the Processes of Production._--Mechanical inventions are typical movers of labor and capital--constant disturbers of what would otherwise be a comparatively tranquil state. Dynamos for generating electricity and devices for conducting it to great distances from its sources have done much to rearrange the society of a score of years ago, as economical steam engines had done at an earlier date. Every device that "saves labor" calls for a _rearrangement of labor_ in the system of organized industry.