The instructions for signalling, determined upon by the electricians of the Telegraphic Construction and Maintenance Company, were as follows:—
1. During the paying-out of the Cable, from the moment of starting until the end is landed at Newfoundland, electrical tests will be applied without intermission.
2. The tests will be for insulation, for continuity, and to determine the resistance of the conductor, the whole length of Cable being joined up in one length.
3. Each series of tests will commence at the hour (Greenwich time), and will last one hour.
4. The insulation test will consist of 30 minutes’ electrification of the Cable, commencing at the hour, and lasting till 30 minutes past the hour. Readings of the galvanometer to be taken every minute, commencing one minute after contact with the battery, the battery to consist of 40 cells.
5. At 30 minutes past the hour signals will be received from the shore for 10 minutes. Unless the ship wishes to communicate with shore by special speaking instruments, in which case, instead of receiving signals from the shore, ship will put on a C to E current to oppose deflection on shore. Galvanometer to arrest shore attention, and when joined, give the call as in paragraph 9: the ordinary signals will be 5 reversals of 2 minutes each.
6. At 40 minutes, C of Cable will be taken to 10 minutes.
7. At 50 minutes signals will be sent to the shore, and for the ordinary signals 5 reversals, 2 minutes each, commencing C to E.
8. Then a repetition of the same tests to be made and continued without any interval.
9. In case it becomes necessary to speak to shore by speaking instruments, the signal will be given at the 50 minutes, and at the 30 minutes, as in paragraph 5, by sending 8¼ minutes’ reversals, commencing Z to E, and changing over to the speaking instruments, on receiving acknowledgment of call from shore (which will be also 8¼ minutes’ reversals), communication or message to be sent, and when acknowledgment of message and reply (if any) is received, then the system of testing is to be resumed, as if no interruption had taken place.