When it came to the exemption of seamen, Admiralty found itself on the
horns of a dilemma. Both the Navy and the merchant service depended in
a very large degree upon the seaman who knew the ropes--who could take
his turn at the wheel, scud aloft without going through the
lubber-hole, and act promptly and sailorly in emergency. To take
wholesale such men as these, while it would enormously enhance the
effectiveness of His Majesty's ships of war, must inevitably cripple
sea-borne trade. It was therefore necessary, for the well-being of
both services, to discover the golden mean. According to statute law
[Footnote: 13 George II. cap. 17.] every person using the sea, of what
age soever he might be, was exempt from the impress for two years from
the time of his first making the venture. The concession did not
greatly improve the situation from a trade point of view. It merely
touched the fringe of the problem, and Trade was insistent.

A further concession was accordingly made. All masters, mates,
boatswains and carpenters of vessels of fifty tons and upwards were
exempted from the impress on condition of their going before a Justice
of the Peace and making oath to their several qualifications. This
affidavit, coupled with a succinct description of the deponent,
constituted the holder's "protection" and shielded him, or was
supposed to shield him, from molestation by the gang. Masters and
mates of colliers, and of vessels laid up for the winter, came under
this head; but masters or mates of vessels detected in running
dutiable goods, or caught harbouring deserters from the fleet, could
be summarily dealt with notwithstanding their protections. The same
fate befell the mate or apprentice who was lent by one ship to
another.