"When a train departs from a railroad station in the night time later than 9 o'clock, and it is deemed necessary to have the mail dispatched by such train, the division superintendent of Railway Mail Service will, where mail is taken from and delivered into the post office by the railroad company, request the company, or where a mail messenger or carrier is employed by the Post Office Department, will direct him, to take the mail to the railroad station at such time as will best serve the interest of the mail service. Such mail will be taken charge of by the agent or other representative of the railroad company, who will be required to keep it in some secure place until the train arrives, and then see that it is properly dispatched." Section 1197, first paragraph. "The division superintendent of Railway Mail Service will give reasonable advance notice to the proper officer of the railroad company, in order that the agent or representatives of the company may be properly instructed." Section 1197, second paragraph. "Railroad companies will be expected to place their mail cars at points accessible to mail messengers or contractors for wagon service. If cars are not so placed the companies will be required to receive the mails from and deliver them to the messengers or contractors at points accessible to the wagon of the messenger or contractor." Section 1198. "A mail train must not pull out and leave mails which are in process of being loaded on the car or which the conductor or trainman has information are being trucked from wagons or some part of the station to the cars." Section 1199. "At all points at which trains do not stop where the Post Office Department deems the exchange of mails necessary, a device for the receipt and delivery of mails satisfactory to the Department must be erected and maintained; and pending the erection of such device the speed of trains must be slackened so as to permit the exchange to be made with safety." Section 1200, first paragraph. "In all cases where the Department deems it necessary to the safe exchange of the mails the railroad company will be required to reduce the speed or stop the train." Section 1200, second paragraph. "When night mails are caught from a crane the railroad company must furnish the lantern or light to be attached to the crane and keep the same in proper condition, regularly placed and lighted; but if the company has no agent or employee at such station, the company must furnish the light, and the care and placing of same will devolve upon the Department's carrier." Section 1200, third paragraph. "The engineer of a train shall give timely notice, by whistle or other signal, of its approach to a mail crane." Section 1200, fourth paragraph.