nine o'clock
`` All right , we 'll see , '' replied Mr Marline , using his stock phrase , and the two continued to walk up and down chatting about other matters , while I went and sat down close to the taffrail , looking out over the sea and wondering what the moaning sound of the ocean meant . I let my imagination wander over the old stories I had heard of the mermaids below , and how they sang their weird songs of lament whenever a storm was coming , anticipating the shipwrecks that would follow and the invasion of their coral caves by the bodies of drowned mortals , over whom they are said to weep tears of pearl ; and , in the flickering light of the stars , that seemed to come from underneath the purple deep and not be shining down from above , I almost fancied I could distinguish the sirens looking up at me from below the water with sad faces , as they combed their long weed-like tresses and raised their wailing croon . Presently , however , I observed the star reflections suddenly disappear from view ; and then , the water grew greyer and greyer , until I was hardly able to see it at all under the stern of the vessel , a hazy obscurity enveloping all below and around . I roused myself with a start , thinking this effect was produced by the gloom of night , and that I had fallen asleep while weaving my quaint fancies anent the mermaidens ; but a couple of sharp strokes of the ship 's bell sounding through the still air at that moment told me it was only nine o'clock . I then recognised the fact that I must seek some other reason for the sombre tone of the sea , as I knew well enough that the little beacons in the sky that had before lit it up , were not in the habit of drawing on their hatches until it was pretty nearly time for the sun to set about getting up for his day 's work , unless something out of the common was going to happen . Looking up , therefore , I was surprised to see a dense black cloud now covering over the heavens like a pall . It must have crept up from somewhere almost instantaneously ; for , twenty minutes before , the sky was clear and bright , while now it was totally obscured from the horizon to the zenith , the angel of darkness seeming to be treading over the face of the deep .