=Federal Administration.=--Federal authority in highway work is vested in the Bureau of Public Roads of the United States Department of Agriculture. The official head is the Secretary of Agriculture, but the administrative head is the Director of the Bureau. In this Bureau are the various instrumentalities needed for carrying on investigations and furnishing information to the various states on highway subjects. The Bureau also supervises the construction of federal aid roads in a general way through district engineers, each of whom looks after the work in several states. Funds for the support of the Bureau of Public Roads are obtained from congressional appropriations to the Department of Agriculture and from a percentage of the funds appropriated for federal aid. Federal aid is money appropriated by Congress to be distributed to the various states to stimulate road construction. It is granted to the states on the condition that the states will expend at least an equal amount on the projects involved. The states in turn usually give a suitable part of the state allotment to each county. There are various limitations as to the amount of federal aid per mile of road and the type of construction that may be employed, but these are matters of regulation that change from time to time. It will be seen that each of the administrative authorities, except the Bureau of Public Roads, is to some extent subservient to a higher authority, and the Bureau of Public Roads is supervised by the United States Congress. Considerable diplomacy is required on the part of any administrative authority if his contact with other officials is to be without friction. This is especially true in connection with the formulation of a policy regarding the types of construction to be adopted for an improvement. The responsibility for the selection is variously placed on the township, county or state authority, the laws not being uniform in this respect. If state or federal funds are allotted to an improvement, the state authority either makes the selection of the type of construction or the selection is made by some subordinate authority subject to the approval of the state highway department. Where the improvement is paid for exclusively with township or county funds, the selection is often made by the township or county authority without review by higher authority. Many abuses have crept into highway administration through the unscrupulous methods of promoters of the sale of road materials or road machinery. A great deal of the selling activity of the agents for these commodities is entirely irreproachable, but it is well known that such is not always the case. As a result, the tendency of legislation is to require the state highway department to approve contracts for materials or construction entered into by the township or county authorities. The state highway departments can secure the requisite technical experts to determine the merits of materials and equipment