While thus waiting he employed his leisure in observations, great and small, of the sort and in the way characteristic of him all through life. One of his rough notes runs thus:—"Cormorants resort in enormous nights, coming in the morning from the northward to Callao Bay, and proceeding along shore to the southward, diving in regular succession one after another on the fish which, driven at the same time from below by shoals of porpoises, seem to have no chance but to be devoured under water or scooped up in the large bags pendent from the enormous bills of the cormorants." "Prodigious seals," we read in another note, "inhabit the rocks, whose grave faces and grey beards look more like the human countenance than the faces of most other animals. They are very unwieldy in their movements when on shore, but most expert in the water. There is a small kind of duck in the bay, which, from the clearness of the water, can be seen flying with its wings under water in chase of small fry, which it speedily overtakes from its prodigious speed."
From note-making of that sort, Lord Cochrane turned to more serious business. The batteries of Callao and of San Lorenzo, a little island in the bay which helped to form the port, mounted one hundred and sixty guns, and more than twice as many were at the command of vessels there lying-to. Direct attack of a force so very much superior to that of the Chilian fleet seemed out of the question. Therefore Lord Cochrane bethought him of a subterfuge. Learning that two North American war-ships were expected at Callao, he determined to personate them with the _O'Higgins_ and _Lautaro_, and so enter the port under alien colours. It was then carnival-time, and on the 21st of February, deeming that the Spaniards were more likely to be off their guard, he proposed "to make a feint of sending a boat ashore with despatches, and in the mean time suddenly to dash at the frigates and cut them out." Unfortunately a dense fog set in, which lasted till the 28th, and made it impossible for him to effect his purpose before the carnival was over. Let the sequel be told in his own words.
"On the 28th, 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. This proved to be a Spanish gunboat, with a lieutenant and twenty men, who, on being made prisoners, informed us that the firing was a salute in honour of the Viceroy, who had that morning been on a visit of inspection to the batteries and shipping, and was then on board the brig-of-war _Pezuela_, which we saw crowding sail in the direction of the batteries. The fog, again coming on, suggested to me the possibility of a direct attack. Accordingly, still maintaining our disguise under American colours, the _O'Higgins_ and _Lautaro_ stood towards the batteries, narrowly escaping going ashore in the fog. The Viceroy, having no doubt witnessed the capture of the gunboat, had, however, provided for our reception, the garrison being at their guns, and the crews of the ships-of-war at their quarters. Notwithstanding the great odds, I determined to persist in an attack, as our withdrawing, without firing a shot, would produce an effect upon the minds of the Spaniards the reverse of that intended. I had sufficient experience in war to know that moral effect, even if the result of a degree of temerity, will not unfrequently supply the place of superior force.