“Exactly,” replied the engineer, “and after measuring the first two distances, as we know the height of the pole, we have only to calculate the proportion in order to find the height of the wall.” The measurements were made with the pole and resulted in determining the distances from the stake to the foot of the pole and the base of the wall to be 15 and 500 feet respectively. The engineer and Herbert then returned to the Chimneys, where the former, using a flat stone and a bit of shell to figure with, determined the height of the wall to be 333.33 feet. Then taking the compasses, and carefully measuring the angle which he had obtained the night before, upon a circle which he had divided into 360 parts, the engineer found that this angle, allowing for the differences already explained, was 53°. Which, subtracted from 90°—the distance of the pole from the equator—gave 37° as the latitude of Lincoln Island. And making an allowance of 5° for the imperfections of the observations, Smith, concluded it to be situated between the 35th and the 40th parallel of south latitude. But, in order to establish the co-ordinates of the island, the longitude also must be taken. And this the engineer determined to do when the sun passed the meridian at noon. They therefore resolved to spend the morning in a walk, or rather an exploration of that part of the island situated to the north of Shark Gulf and the lake; and, if they should have time, to push on as far as the western side of South Mandible Cape. They would dine on the downs and not return until evening. At half-past 8 the little party set out, following the edge of the channel. Opposite, upon Safety Islet, a number of birds of the sphemiscus family strutted gravely about. There were divers, easily recognizable, by their disagreeable cry, which resembled the braying of an ass. Pencroff, regarding them with gastronomic intent, was pleased to learn that their flesh, though dark colored, was good to eat. They could also see amphibious animals, which probably were seals, crawling over the sand. It was not possible to think of these as food, as their oily flesh is detestable; nevertheless Smith observed them carefully, and without disclosing his plans to the others, he announced that they would very soon, make a visit to the island. The shore followed by the colonists was strewn with mollusks, which would have delighted a malacologist. But, what was more important, Neb discovered, about four miles from the Chimneys, among the rocks, a bed of oysters, left bare by the tide. “Neb hasn’t lost his day,” said Pencroff, who saw that the bed extended some distance. “It is, indeed, a happy discovery,” remarked the reporter. “And when we remember that each oyster produces fifty or sixty thousand eggs a year, the supply is evidently inexhaustable.” “But I don’t think the oyster is very nourishing,” said Herbert.