HOLYHEAD. — The s.s. Dahomey, of London, bound from Liverpool for West Africa, with a general cargo, stranded on the rocks between the breakwater and the North Stack in a thick fog, on the night of the 6th April. On receipt of intelligence of the casualty, the steam Life-boat Duke of Northumberland, at about 10.15, proceeded to the vessel, and first of all took off the passengers nine in number and four of the crew. Having safely landed them, the Life-boat returned to the vessel and found that a steam-tug had arrived and was ready to render any assistance. The mails having been taken on board the Life-boat and landed, another trip was made with the parcel post packages and the passengers' luggage, and on returning once more to the vessel the master and Lloyd's agent requested her to remain by, and she accordingly stayed until about 7 o'clock in the morning..