appearance, preparations were made to put in execution a plan which had
been formed to attack the Spanish shipping during the Carnival, when, in
the height of that festival, less vigilance than ordinary might
reasonably be expected. We had previously ascertained that the naval
force in the harbour consisted of the frigates _Esmeralda_ and
_Venganza_, a corvette, three brigs of war, a schooner, twenty-eight
gun-boats, and six heavily-armed merchantmen; the whole being moored
close in under the batteries, which mounted upwards of 160 guns, whilst
the aggregate force of the shipping was 350 guns, as appeared from an
official account of their armament.

A direct attack with our small force seemed, therefore, a thing not at
present to be attempted; but in its place I had formed the design to cut
out the frigates during the carnival, which terminated on the 23rd.
Knowing that two North American ships of war were daily expected at
Callao, it was arranged to take in the _O'Higgins_ and _Lautaro_, under
American colours, leaving the _San Martin_ out of sight behind San
Lorenzo, and if the _ruse_ were successful, to make a feint of sending a
boat ashore with despatches, and in the meantime suddenly to dash at the
frigates, and cut them out. Unfortunately, one of those thick fogs, so
common on the Peruvian coast, arose, in which the _Lautaro_ parted
company, and did not rejoin the flag-ship for four days afterwards,
when the carnival being at an end, our plan was rendered abortive.

The fog, which in the climate of Peru often continues for a considerable
length of time, lasted till the 29th, when hearing heavy firing, and
imagining that one of the ships was engaged with the enemy, I stood with
the flag-ship into the bay; the other ships, imagining the same thing,
also steered in the direction of the firing, when the fog clearing for a
moment, we discovered each other, as well as a strange sail near us;