Section 19. The commissioners severally may, at other times than at regular meetings, receive petitions relative to railroads or to matters where the county has no interest and may take recognizances thereon, and, upon such petitions and similar petitions entered at a regular meeting the commissioners or the chairman may, at other times than at regular meetings, appoint hearings and direct notices to be given to persons interested. They shall severally make return of such petitions and recognizances, with their proceedings, at any regular or special meeting held therefor; and the clerk shall record the same. The costs of any such special meeting shall be paid by such parties as the commissioners determine.