Section 87. Mails

Any railroad corporation shall, when applied to by the
  postmaster-general, convey the mails of the United States on  its  road,
  and  in case such corporation and the postmaster-general shall not agree
  as to the rate of transportation therefor, and as to the time,  rate  of
  speed,  manner  and  condition of carrying the same, the commissioner of
  transportation shall fix the  prices,  terms  and  conditions  therefor,
  after  giving  the  corporation reasonable opportunity to be heard. Such
  price shall not be less for carrying such mails in the regular passenger
  trains than the amount which such corporation would receive  as  freight
  on a like weight of merchandise transported in their merchandise trains,
  and   a   fair   compensation   for   the   post-office   car.   If  the
  postmaster-general shall require the mail to be carried at other  hours,
  or  at  higher  speed than the passenger trains are run, the corporation
  shall furnish an extra train for the  mail,  and  be  allowed  an  extra
  compensation  for  the  expenses  and wear and tear thereof, and for the
  service to be fixed as herein provided.
    Every railroad corporation refusing or neglecting to comply  with  any
  provision  of  this section shall forfeit to the people of the state one
  hundred dollars for every day such neglect or refusal continues.