'Rob,' said he, in a whisper, as he fastened the painter of his punt, 'I promised I would tell ye something. I'll show ye how to find the herring.' 'You!' said Rob, derisively. 'Ay, me, Rob, I'll make a rich man of you. I will tell you something about the herring that not any one in Erisaig knows--that not any one in Scotland knows.' 'Why havena ye made a rich man of yourself, Sandy?' said Rob, with more good nature. The half-witted creature did not seem to see the point of this remark. 'Ay, ay,' he said, 'many is the time I was thinking of telling this one or telling that one; but when I would go near it was always "Daft Sandy!" and "Daft Sandy!" and there was always the peltin' wi' the broken herring--except from you, Rob. And I was saying to myself that when Rob MacNicol has a boat of his own, then I will show him how to find the herring, and no one will know but himself.' By this time the MacNicols had taken to their oars again; and they had pulled outside the harbour, the old punt still astern. Then Rob had to speak plainly. 'Look here, Sandy, I will not put ye ashore by force. But I canna have your punt at the stern of the boat. It'll be in the way of the nets.' But the old man was more eager than ever. If they would only pull into the bay hard by, he would anchor the punt and leave it. He begged Rob to take him for that night's fishing. He had discovered a sure sign of the presence of herring--unknown to any of the fishermen. What was the phosphorescence in the sea?--the nights were too clear for that. What was the mere breaking of the water?--a moving shoal that might escape. But this sign that the old man had discovered went to show the presence of large masses of the fish, stationary and deep: it was the appearance on the surface of the water of small air-bubbles. He was sure of it. He had watched it. It was a secret worth a bankful of money. And again, he besought Rob to let him accompany him; Rob had stopped the lads when they were throwing herring at him; Rob alone should have the benefit of this valuable discovery of his. Rob MacNicol was doubtful; for he had never heard of this thing before; but he could not resist the importunities of the old half-witted creature. They pulled in and anchored the punt; then they set forth again, rowing slowly as the light faded out of the sky, and keeping a watch all around on the almost glassy seas. There was no sign of any herring; no solan geese sweeping down; no breaking of the water; and none of the other boats, so far as they could make out, had as yet shot their nets. The night was coming on, and they were far away from Erisaig; but still old Sandy kept up his watch, studying the surface of the water, as if he expected to find pearls floating there. And at last, in great excitement, he grasped Rob's arm. Leaning over the side of the boat, they could just make out in the dusk a great quantity of minute air-bubbles rising to the surface of the sea.