It is hereby made the duty of railroad conductors and brakemen without warrant or other process to arrest immediately any person violating on railroad trains any of the provisions of the preceding section, and to call upon all bystanders or others for assistance, when the same may be necessary, to enable them to make such arrest, and when such offense is committed on any railroad car, coach or train, the venue shall lie and the person be tried in any county through which said railroad may run, not outside the judicial district in which the offense was committed.

R.L. 1910, § 2501.