Felix thought that the water had lost its clearness and had become thick, which he put down to the action of the wavelets disturbing the sand in the shallows.  Ahead the haze, or mist, was now much thicker, and was apparently not over a mile distant.  It hid the islands and concealed everything.  He expected to enter it immediately, but it receded as he approached.  Along the strand of an island he passed there was a dark line like a stain, and in still water under the lee the surface was covered with a floating scum.  Felix, on seeing this, at once concluded that he had unknowingly entered a gulf, and had left the main Lake, for the only place he had ever seen scum before was at the extremity of a creek near home, where the water was partly stagnant on a marshy level.  The water of the Lake was proverbial for its purity and clearness.

He kept, therefore, a sharp look-out, expecting every moment to sight the end of the gulf or creek in which he supposed himself sailing, so that he might be ready to lower his sail.  By degrees the wind had risen till it now blew with fury, but the numerous sandflats so broke up the waves that he found no inconvenience from them.  One solitary gull passed over at a great height, flying steadily westwards against the wind.  The canoe now began to overtake fragments of scum drifting before the wind, and rising up and down on the ripples.  Once he saw a broad piece rise to the surface together with a quantity of bubbles.  None of the sandbanks now rose more than a foot or so above the surface, and were entirely bare, mere sand and gravel.

The mist ahead was sensibly nearer, and yet it eluded him; it was of a faint yellow, and though so thin, obscured everything where it hovered.  From out of the mist there presently appeared a vast stretch of weeds.  They floated on the surface and undulated to the wavelets, a pale yellowish green expanse.  Felix was hesitating whether to lower his sail or attempt to drive over them, when, as he advanced and the mist retreated, he saw open water beyond.  The weeds extended on either hand as far as he could see, but they were only a narrow band, and he hesitated no longer.  He felt the canoe graze the bottom once as he sailed over the weeds.  The water was free of sandbanks beyond them, but he could see large islands looming in several directions.

Glancing behind him he perceived that the faint yellow mist had closed in and now encircled him.  It came with two or three hundred yards, and was not affected by the wind, rough as it was.  Quite suddenly he noticed that the water on which the canoe floated was black.  The wavelets which rolled alongside were black, and the slight spray that occasionally flew on board was black, and stained the side of the vessel.  This greatly astonished and almost shocked him; it was so opposite and contrary to all his ideas about the Lake, the very mirror of purity.  He leant over, and dipped up a little in the palm of his hand; it did not appear black in such a small quantity, it seemed a rusty brown, but he became aware of an offensive odour.  The odour clung to his hand, and he could not remove it, to his great disgust.  It was like nothing he had ever smelt before, and not in the least like the vapour of marshes.