One curious episode deserves mention. In the earlier days of the Famine, news reached the Australian ports that certain of the Polynesian islands were still free from the scourge; and a frenzied emigration followed. But each ship carried with it the freight of _B. diazotans_, so that this exodus merely served to spread the bacilli into spots which otherwise they might not have reached. Before very long the whole of Polynesia was involved in the disaster. Some diaries have been discovered on board deserted vessels; and in every case the history is the same: the long search through devastated islands, the discovery at last of some untouched spot in the ocean wilderness, the rejoicings, the landing, and then, a few days later, the realisation that here also the bacillus had made its appearance. What seems most curious is the fact that in many cases it was weeks before the ship’s company grasped the apparently obvious truth that their own appearance coincided with the arrival of the fatal germs. It never seems to have occurred to any of them that they bore with them the very thing which they were trying to escape. So they went from island to island, seeking refuge from a plague which stood ever at their elbow, until at last their stores failed. On the West Coast of South America a new phenomenon appeared. The huge deposits of nitrates in Bolivia and South Peru formed the best breeding-ground for _B. diazotans_ which had yet been detected, with the result that nitrogen poured into the atmosphere in unheard-of volumes. In most places the winds were sufficient to disperse these invisible clouds of gas; but in some spots the arrival of the bacilli coincided with a dead calm, so that the nitrogen remained in the neighbourhood in which it was generated. The great salt swamp in the Potosi district furnished the best example of this phenomenon. The whole surface frothed and boiled for days together; and the atmosphere in the neighbourhood became so heavily charged with nitrous fumes that the air was almost unbreatheable. All the inhabitants of the district fled before this, to them, inexplicable danger; and the effects extended as far as Llica and the railway junction at Uyuni. In this “caliche” district, the destruction of combined nitrogen probably attained its maximum; and the propagation of _B. diazotans_ never reached such a level in any other part of the world.