_The Liberation of Capital by Invention._--For a long period it was the general rule that a mechanical invention at first called capital to the point at which it was applied, although it afterward created new capital and sent it away to make more than good the draft it originally made. This rule is no longer universally applicable. When an invention cheapens capital goods, it liberates capital. It is clear that a hundred and twenty-five years ago there was small chance that an invention would liberate very much capital by reducing the cost of making tools, buildings, rails, machinery, etc., since there were so few of them to cheapen. Now that machines are at hand in myriad forms the chance is large that an invention will substitute for many of them others of less costly construction. It will in these cases cause less capital to be required per machine than was formerly needed. _Simplifying the Forms of Machinery and Cheapening the Materials of It._--The history of invention shows that the early machines sometimes took cumbersome and expensive forms, for which simple and cheaper forms were later substituted. Much simplifying of mechanical appliances is all the while going on, and this, of course, liberates some capital. Making instruments of any kind out of cheaper materials has the same effect that anything has which reduces the cost of constructing the instruments. Bessemer steel has made rails, bridges, ships, buildings, steam boilers, and a vast number of mechanical tools and appliances less costly than they were, and so has liberated some of the capital which such things formerly embodied. After one of the machines of the costlier type has earned the fund on which its owner relies for replacing it as it is worn out, it appears that a part of this fund will suffice for procuring a perfectly good substitute for it, and the remainder may be used for procuring other appliances of production. _A'''_ _B'''_ _C'''_ _H'''_ _A''_ _B''_ _C''_ _H''_ _A'_ _B'_ _C'_ _H'_ _A_ _B_ _C_ _H_