By this means the local authorities are brought into close relationship with the central head, and the centrifugal influences of independent interests and customs are counteracted by the force of central attraction. Centralization increases the importance of the whole body, and, like the pendulum of a clock, regulates the movements of the whole State. In some cases it tends to make the government despotic, when the local governments are entirely under the control of the central; and every enactment, and scheme, and plan checked and supervised by the chief officers of the State. Such was the system adopted in France by Napoleon III. But cohesion without the enforcement of a hard and rigid connection, a general supervision without severe tyrannical jurisdiction, are the best methods of securing the unity of composite States. But the force of cohesion is evidently at work in the nation apart from centralization. Men who have a community of interests unite together for the purposes of strength and mutual assistance. They combine for the sake of securing means of support in sickness, and form benefit societies, such as the Order of Oddfellows or Foresters. This force of cohesion has produced trade unions, and similar institutions which exist for the purpose of protecting a common interest, and giving expression to the concurrent opinions of the members. These have their legitimate use in every civilized State, in spite of some of the disadvantages which follow in their train. There are, of course, opposed interests in every community: _attractive_ forces, which produce trade unions, guilds, corporations, companies, and the like; and _repulsive_ forces, which result from the opposed interests of employers and employed, landlords and tenants, and similar pairs of different classes in the community. As time goes on, and the State advances with it, these forces will gain in strength; the cohesion of classes will become greater; association will grow as naturally as the bubbles form on the surface of our evening beverage. It is a law of nature, and therefore cannot be resisted. But the repulsive forces will be no less strong, and to calculate the resultant of these contending interests will be the problem for practical statesmen to solve.