The requirements of a valid contract, as previously stated, control most of the relations which the employer has with his employees. Contracts for labor, unless for more than one year, need not be in writing. If, however, the service to be rendered is unusual, the agreement should be reduced to writing, because, in the absence of specific agreement, the law assumes that customary service and wages are implied. Like all other employers of labor the farmer is under obligation to protect his workman from injury. He must not subject them to unusual and unreasonable risks. He must hire workmen suited to the employment. For example, if he employs a young boy to drive a fractious horse, he would be liable for any injury that might occur. In like manner, he must exercise proper care concerning the safety of the machinery placed in the hands of his workmen. He must keep his premises in a safe condition and must not expose his workmen to risks not incident to the employment for which they are hired. The farmer is liable in damages for the acts of his workmen which are within the scope of their employment, although the authority may not have been expressly conferred. "He who acts by another acts himself." In case one is sued for the acts of his employee, the burden is upon him to prove that the act of the workman was without authority, expressed or implied. ----- [D] Haigh's "Manual of Law," p. 69. CHAPTER XXI RURAL LEGISLATION Various laws have been enacted by federal and state legislatures for the better protection of producer and consumer. Much of this legislation affects in a very special way the interests of the farmer. Not infrequently, in fact, generally, the state department of agriculture has more or less direct jurisdiction over their enforcement. State departments of agriculture usually publish a collection of the laws of this character. These laws vary greatly in the different states and only the most general outline, as they affect the interests of the farmer, can be given here. Persons can inform themselves as to the details as enforced in a given state by applying to the state secretary of agriculture.