It shall be the duty of the mayor, or principal executive officer, and heads of departments of every city, village or municipality to aid the civil service commission in all proper ways in carrying out the provisions of this act, and to allow the reasonable use of public buildings and to cause suitable and convenient rooms and accommodations to be assigned and provided, and to be furnished, heated and lighted for carrying on the work and examinations of the civil service commission and in all proper ways to facilitate the same. The civil service commission may order from the proper authorities the necessary stationery, postage stamps, official seal and other articles to be supplied, and the necessary printing to be done, for its official use.