indeed, was the last, that our young man was not without the hope he would be able to keep under the lee of the shoals until the gale broke, and then beat up through them, and still come to his rescue.  There was one point, in particular, on which Mark felt unusual concern.  Bob knew nothing whatever of navigation.  It was impossible to teach him anything on that subject.  He knew the points of the compass, but had no notion of the variations, of latitude or longitude, or of anything belonging to the purely mathematical part of the business.  Twenty times had he asked Mark to give him the latitude and longitude of the crater; twenty times had he been told what they were, and just as often had he forgotten them.  When questioned by his young friend, twenty-four hours after a lesson of this sort, if he remembered the figures at all, he was apt to give the latitude for the longitude, or the longitude for the latitude, the degrees for the minutes, or the minutes for the degrees.  Ordinarily, however, he forgot all about the numbers themselves.  Mark had in vain endeavoured to impress on his mind the single fact that any number which exceeded ninety must necessarily refer to longitude, and not to latitude; for Bob could not be made to remember even this simple distinction.  He was just as likely to believe the Reef lay in the hundred and twentieth degree of latitude, as he was to fancy it lay in the twentieth.  With such a head, therefore, it was but little to be expected Bob could give the information to others necessary to find the reef, even in the almost hopeless event of his ever being placed in circumstances to do so.  Still, while so completely ignorant of mathematics and arithmetic, in all their details, few mariners could find their way better than Bob Betts by the simple signs of the ocean.  He understood the compass perfectly, the variations excepted; and his eye was as true as that of the most experienced artist could be, when it became necessary to judge of the colour of the water.  On many occasions had Mark known him intimate that the ship was in a current, and had a weatherly or a lee set, when the fact had escaped not only the officers, but the manufacturers of the charts.  He judged by ripples, and sea-weed, and the other familiar signs of the seas, and these seldom failed him.  While, therefore, there was not a seaman living less likely to find the Reef again, when driven off from its vicinity, by means of observations and the charts, there was not a seaman living more likely to find it, by resorting to the other helps of the navigator.  On this last peculiarity Mark hung all his hopes of seeing his friend again, when the gale should abate.

Since the moment when all the charge of the ship fell upon his shoulders, by the loss of Captain Crutchely, Mark had never felt so desolate, as when he lost sight of Bob and the Neshamony.  Then, indeed, did he truly feel himself to be alone, with none between him and his God with whom to commune.  It is not surprising, therefore, that one so much disposed to cherish his intercourse with the Divine Spirit, knelt on the naked rock and prayed.  After this act of duty and devotion, the young man arose, and endeavoured to turn his attention to the state of things around him.