Mackinnon was famous for practical jokes; which were, however, always
played in a gentlemanly way. Before landing at St. Andero's, with some
other officers who had been on leave in England, he agreed to personate
the Duke of York, and make the Spaniards believe that his Royal Highness
was amongst them. On nearing the shore, a royal standard was hoisted
at the masthead, and Mackinnon disembarked, wearing the star of his
shako on his left breast, and accompanied by his friends, who agreed
to play the part of aides-de-camp to royalty. The Spanish authorities
were soon informed of the arrival of the Royal Commander-in-Chief of
the British army; so they received Mackinnon with the usual pomp and
circumstance attending such occasions. The mayor of the place, in honour
of the illustrious arrival, gave a grand banquet, which terminated with
the appearance of a huge bowl of punch. Whereupon Dan, thinking that
the joke had gone far enough, suddenly dived his head into the porcelain
vase, and threw his heels into the air . The surprise and indignation
of the solemn Spaniards was such, that they made a most intemperate
report of the hoax that had been played on them to Lord Wellington;
Dan, how- ever, was ultimately forgiven, after a severe reprimand.

Another of his freaks very nearly brought him to a court- martial.
Lord Wellington was curious about visiting a convent near Lisbon, and
the lady abbess made no difficulty; Mackinnon, hearing this, contrived
to get clandestinely within the sacred walls, and it was generally supposed
that it was neither his first nor his second visit. At all events, when
Lord Wellington arrived, Dan Mackinnon was to be seen among the nuns,
dressed out in their sacred costume, with his head and whiskers shaved,
and as he possessed good features, he was declared to be one of the
best-looking amongst those chaste dames. It was supposed that this
adventure, which was known to Lord Byron, suggested a similar episode