When any controversy or difference not involving questions which may be the subject of a civil action, exists between an employer, whether an individual, copartnership or corporation, employing not less than 25 persons, and his employees in this State, the Department of Labor shall upon application as herein provided, and as soon as practicable thereafter, visit the locality of the dispute and make a careful inquiry into the cause thereof, hear all persons interested therein who may come before it, advise the respective parties what, if anything ought to be done or submitted to by both to adjust the dispute, and make a written decision thereof. This decision shall at once be made public, shall be recorded upon proper books of record kept by the Department of Labor, and a short statement thereof published in the annual report hereinafter provided for, and the Department shall cause a copy thereof to be filed with the clerk of the city, town or village where said business is carried on.