Passengers in all classes were provided with a numbered contract ticket with all the booking details, including several individual names/ages if applicable, plus the detailed list of contractual obligations. Each ticket had a tear-off 'counterpart' section on which these details were duplicated. This was to be removed and presented to the emigration officer at the port of embarkation, while the remainder of the ticket was to be retained at least until the voyage was over.
3rd Class passengers were required to give up the detachable 'counterpart' section directly to an emigration official during the inspection procedures before boarding, and were provided with their individual medical inspection cards in return. These served also as boarding passes.
Contract tickets supplied to cabin passengers had a similar detachable 'counterpart', but this need not be given up until after they had boarded, when it was the responsibility of the ship's owners or master (rather than the cabin passengers themselves) to pass these slips of paper on to the emigration officials.
So the cabin passengers, having escaped the emigration inspection onshore, needed a separate boarding pass. This was sent in advance along with the contract ticket. Unlike the tickets, these passes were not numbered and did not even have space for filling in the passenger's name - just the vessel's name and the sailing date. The sole surviving (unused) pass, however, does have the Reverend Holden's name written rather untidily across the top. I'd guess that a card was provided for each individual, and that they were collected from them as the passengers boarded.
The letter sent to Frank Browne mentions that a 'pass' was enclosed, which was presumably a standard, un-numbered boarding card. It's not clear whether a ticket was enclosed as well, but since Browne was travelling only from one part of Britain to another, he wouldn't have needed to produce a ticket 'counterpart' for the emigration officials. He had been provided with a boarding pass and a letter of introduction to the Purser. If his passage had been specially arranged as a freebie, maybe that's all he needed.
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