And turn up she did, shortly after midnight on the fifth night following our arrival upon our cruising ground.  The moon was by that time approaching her second quarter, was well above the horizon by sunset, and was affording enough light to enable us to distinguish the rig and chief characteristics of a vessel eight miles away.  To my very great gratification it was the look-out aboard the _Dolphin_ who first sighted her, she being at that time hull-down in the south-western quarter and reaching athwart our hawse on the starboard tack; thus as the _Eros_ and ourselves were hove-to, also on the starboard tack, she rapidly neared us.  At first the only thing that we could clearly distinguish was that she was a full-rigged ship--as were the _Virginia_ and the _Preciosa_-- but, even so, there were certain details connected with her rig which, while not being exactly peculiar, corresponded with similar details referred to in the description of the two notorious slavers, as ascertained by Captain Perry; I therefore made a lantern signal to the _Eros_--under the shelter of our mainsail, so that the stranger to leeward might not see our lights and take the alarm--calling attention to the fact that there was a suspicious sail in sight to the south-west; and this signal was simply acknowledged without comment.  But I saw that almost immediately afterwards the _Eros_ swung her main-yard, boarded her fore and main tacks, and hauled to the wind with the object, of course, of preventing the strange sail from working out to windward of us; and a few minutes later I got a signal from the commodore instructing me to remain hove-to for the present, and, later, to act as circumstances might require.