"I never practise upon anybody's credulity in matters of that sort," said the doctor. "If a young man likes to believe that the moon is made of green cheese, I may let him; but atmospheric and scientific facts are above being trifled with. Well, if you go through this gap, which is barely a mile off, you will find a very pretty place--the wells, and sycamore trees, and dates. Just the place to spend a happy day. And if you take a bottle or two of champagne, and a _pate de foie gras_, I shall not mind if I make one of the party, and show you the objects of interest." But such a pic-nic was not destined to come off, nor was there even any opportunity given for testing the coral theory, for there was plenty of work to be done at the moment, and on the eleventh the intending pleasure-seekers started for Baker's zereba at six o'clock in the evening. Baker Pasha's Egyptians, though they had not proved much good at fighting, and had paid the penalty of their cowardice by undergoing a massacre which made the world thrill with horror, were very useful to the avenging force which followed so quickly on their traces. The fort they had constructed near Trinkitat had done much to help the rapid and successful advance upon Tokar; and now the zereba they had made eight miles out from Suakim, and in the direction in which Osman Digna lay with his whole army, made a good first halting-place for the English troops. A zereba, it should be mentioned, is an enclosed space surrounded by thorn-covered bushes cut down and packed round it, with old packing-cases, or anything else which will afford cover to those inside. This one was particularly strong, being further protected by a mound of earth all round it. When the force, which was the same as before, with the addition of two hundred Marines, and a mule battery of four nine-pounders, had gone some little way, night fell, but not darkness, for a bright moon lent them her rays. Not such a moon as we are accustomed to in these latitudes, but a large brilliant orb, by whose light small print might be easily read. "You have got the best of it," said MacBean, who rode up first to one friend amongst the officers and then to another, detailing information which he managed to pick up, he himself best knew how; but it was, as a rule, exceptionally correct. "The Highlanders, who marched out to the zereba yesterday in the heat, suffered awfully. There were five cases of sunstroke, and lots of other men had a narrow squeak of being bowled over too." "I can easily imagine it," replied Major Elmfoot, "for it was hot enough in camp." "It is not exactly what you would call bracing to-night, even," said Fitzgerald.