On the 9th of August, the fleet reached Gibraltar, where the Minden had arrived only the preceding night. Here they found a Dutch squadron of five frigates and a corvette, commanded by Vice-Admiral the Baron Von de Capellan, who, on learning the object of the expedition, solicited and obtained leave to co-operate. The ships, having completed their ordnance stores and provisions, were ready to sail on the 12th; but the strong easterly wind prevented them from moving for two days. On the 13th, every ship received a plan of the fortifications, with full instructions respecting the position she was to occupy. A general order to this effect had been issued on the 6th, but the co-operation of the Dutch squadron had made some change in the arrangements necessary. To this squadron was assigned the duty of attacking the fort and batteries south of the town, a service previously intended for the Minden and Hebrus, which were now to take a position among their consorts in front of the Mole.
The fleet sailed next day, and on the 16th was within two hundred miles of its destination, when the wind again shifted to the eastward. That evening the ship-sloop Prometheus, Captain Dashwood, joined direct from Algiers, with information that the Algerines were making every preparation to meet the attack. All the former defences had been made completely effective, and new works had been added; forty thousand troops had been assembled; all the Janizaries called in from distant garrisons; and the whole naval force of the regency, four frigates, five large corvettes, and thirty-seven gun-boats, were collected in the harbour. The Prometheus brought the wife, daughter, and infant child of Mr. M’Donell, the British consul. The two former had succeeded in getting off, disguised as midshipmen; but the infant, which had been carefully concealed in a basket, after a composing medicine had been given to it by the surgeon of the Prometheus, awoke, and cried as it was passing the gateway, and thus led to the arrest of all the party then on shore. The child was sent off next morning by the Dey, and, “as a solitary instance of his humanity,” said Lord Exmouth, “it ought to be recorded by me;” but the consul was confined in irons at his house, and the surgeon, three midshipmen, and fourteen seamen of the Prometheus, were detained as prisoners; nor could the most urgent remonstrances of Captain Dashwood induce the Dey to release them.