Sec. 934-1a. [=Penalty.=] Whoever, being the owner, operator, lessee or agent of a coal mine where ten or more persons are employed, fails or neglects, after ninety days from the taking effect of this act, to comply with the provisions of section 934-1 of the General Code, or violates any of the provisions thereof, shall be fined not less than two hundred nor more than five hundred dollars. (This act became effective June 16, 1921.) (109 O.L. 22.) Sec. 934-2. [=Owner, lessee or agent shall install telephone system.=] Every owner, operator, lessee or agent of a coal mine, where twenty or more persons are employed, shall install, and maintain in efficient working condition, a telephone connecting each main switch of such mine with an outside telephone so connected and maintained as to permit communication with persons outside of the mine with persons on the main switch or switches or other points inside of the mine that may be designated by the district mine inspector. Sec. 934-3. [=Penalty.=] Whoever, being the owner, operator, lessee or agent of a coal mine, where twenty or more persons are employed, fails or neglects, after six months from the taking effect of this act, to comply with the provisions of section 934-2 of the General Code, or violates any of the provisions thereof, shall be fined not less than two hundred nor more than one thousand dollars. (This act became effective June 22, 1921.) (109 O.L. 48-49.) Sec. 935. [=Owner or lessee shall make map of mine.=] The owner, lessee or agent of a mine having an excavation of fifteen thousand cubic yards, or more, shall cause to be made, on a scale of not less than two hundred feet per inch, an accurate map thereof, which shall show the following: The boundary lines and names of the owners of the surface of each tract under which excavation is made, and for not less than five hundred feet contiguous thereto, and under which excavations are likely to be made during the ensuing year, together with all streams and bodies of standing water; the township and county lines coming within the limits of such map, with the name of each plainly marked close to and parallel with such lines; the title, the name or number of the mine, or both, the township and county in which located; the section lines, with the number of each, marked plainly within the sections; the location of the mine openings, railroad tracks, public highways, oil and gas wells, magazines and buildings, and plainly marked with name of each; the location and extent of the excavations and connection with the surface survey; the direction of the air current, or air currents by arrows; the location and extent, so far as known or obtainable, of the excavation of any other mine or mines within the limits of the map; the boundary lines of the tracts of coal owned or leased within the limits of the map; the elevation of the floor of the excavation, above mean tide at Sandy Hook, at or near the boundary line or lines