What could David Bruce do, but salute, and withdraw from his Presence? He had schemed, he had begged, and pulled wires, finally he had dared the anger of this Jupiter, so that he might go hunt microbes in South Africa. It was in the early eighteen nineties; Theobald Smith, in America, had just made that revolutionary jump ahead in microbe hunting--he had just shown how death may be carried by a tick, and only by a tick, from one animal to another. And now this David Bruce, physically as adventurous as Theobald Smith was mildly professorial, wanted to turn that corner after Smith.... Africa swarmed with mysterious viruses that made the continent a hell to live in; in the olive-green mimosa thickets and the jungle hummed and sizzled a hundred kinds of flies and ticks and gnats.... What a place for discoveries, for swashbuckling microscopings and lone-wolf bug-huntings Africa must be! It was in the nature of David Bruce to do things his superiors and elders didn’t want him to do. Just out of medical school in Edinburgh, he had joined the British Army Medical Service, not to fight, nor to save lives, nor (at that time) to get a chance to hunt microbes--not for any such noble objects. He had joined it because he wanted to marry. They hadn’t a shilling, neither Bruce nor his sweetheart; their folks called them thirteen kinds of romantic idiots--why couldn’t they wait until David had established himself in a nice practice? So Bruce joined the army, and married on a salary of one thousand dollars a year. In certain ways he was not a model soldier. He was disobedient, and, what is much worse, tactless. Still a lieutenant, he one day disapproved of the conduct of his colonel, and offered to knock him down.... If you could see him now, past seventy, with shoulders of a longshoreman and a barrel-chest sloping down to his burly equator, if you could hear him swear through a mustache Hindenburg would be proud to own, you would understand he could, had it been necessary, have put that colonel on his back, and laughed at the court-martial that would have been sure to follow. He was ordered to the English garrison on the Island of Malta in the Mediterranean; with him went Mrs. Bruce--it was their honeymoon. Here again he showed himself to be things soldiers seldom are. He was energetic, as well as romantic. There was a mysterious disease in the island. It was called Malta fever. It was an ill that sent pains up and down the shin bones of soldiers and made them curse the day they took the Queen’s shilling. Bruce saw it was silly to sit patting the heads of these sufferers, and futile to prescribe pills for them--he must find the cause of Malta fever!