The promoters of tramways authorized by special Act and their lessees may use on their tramways carriages with flange wheels or wheels suitable only to run on the rail prescribed by such Act; and, subject to the provisions of such special Act and of this Act, the promoters and their lessees shall have the exclusive use of their tramways for carriages with flange wheels or other wheels suitable only to run on the prescribed rail.

All carriages used on any tramway shall be moved by the power described by the special Act, and where no such power is prescribed, by animal power only.

No carriage used on any tramway which is hereafter authorized by special Act shall extend beyond the outer edge of the wheels of such carriage more than eleven inches on each side.