We have come to that stage of human progress when we could not return to the Crusoe method if we desired. We must depend upon our brothers in distant parts. A vast industrial machine has been created, of which each member of the human family forms a part. A must look to B for his shoes, B must look to C for his meat, C must look to D for his coal, and all must look to one another for every needed thing. Even the savages in distant lands are at work procuring ivory and other commodities for us while we are creating suitable articles for them, and thus the human family are co-operating together for the common good. If this system of co-operation or trade is not interfered with by unnatural and artificial devices, every man will sooner or later find his level and bend his energies in that calling to which he is best fitted by nature, education, training, and environment. A natural law is at work. To interfere with it is to divert commerce from its natural channels and cause friction in the great industrial machine. The machine needs no oiling or mending; it simply requires direction. It develops, expands and lubricates as it runs. It is not revolution that wears out a machine; it is friction. COMBINATION. Two or more persons can enjoy the heat of one stove, or the light of one lamp, or the shelter of one roof, as well as one person, and without depriving anyone of an equal quantity thereof. A printer can produce 1,000 circulars with but little more cost than 50. A truck or car can carry tons with but little more expense than pounds. Two fish can be fried in one pan as well as one. A professor can teach a class of 500 as well as of five. Hence the advantages of combination and co-operation, and hence the uneconomy of individual isolation. How much wiser for Crusoe to take Friday in his household and divide their labors, each doing that which best suits him, using,--so to speak--only one stove, one lamp and one frying-pan.