This theory, no doubt, agrees with certain well-known facts. In a tropical climate, if soil which has been long undisturbed, or the soil of marshy ground, be turned up, intermittent fever is almost certain to ensue. In illustration of this, I recollect that at Hong Kong the troops were unhealthy, and a beautiful position on a peninsula exposed to the most favorable sea-breezes was selected for a new encampment. The troops were encamped upon this spot for some time to test its healthiness, which was found to be all that could be desired. It was then resolved to build barracks. As soon as the foundations were dug, fever broke out. As an instance of this nearer home, I may mention that last winter at Cannes, in the south of France, some extensive works adjacent to the town were begun which required a large quantity of earth to be moved. The weather was exceptionally warm; an outbreak of fever occurred among the workmen, of whom fifteen died. This fever was attributed to the turning up of the soil. If a strong solution of quinine be let fall in the water containing these organisms they at once die; the efficacy of quinine as a preventive of this form of fever would therefore not be inconsistent with this theory. Upon this subject the President called attention to the view of Sir Joseph Fayrer, who acknowledged the importance of the discovery if it should be confirmed, but considered that there was a possibility that the results attributed to these influences might, to some extent, be due to disturbance of the system in a body predisposed to be deranged by peculiarity of constitution, climatic or other influence of the nature of which we are ignorant, though it is conceivable by analogy. The marvelous facility of reproduction of various germs, as shown by Pasteur in the case of chicken cholera, was dwelt upon; and the President said that it would be a wonder how any higher form of life could exist subject to the possibility of invasion by such countless hosts of occult enemies were it not seen that the science of the prevention of disease advanced quite as rapidly as our knowledge of the causes. Holding that the attitude of the sanitarian, in regard to the germ theory of diseases, as applied to all diseases of the zymotic class, must be one of reserve, yet, he said, even if the views of those who are prepared to accept the germ theory of disease to its fullest extent were shown to be true, it seems to be certain that if the invasion of these occult enemies present in the air is undertaken in insufficient force, or upon an animal in sufficiently robust health, they are refused a foothold and expelled; or, if they have secured a lodgment in the tissues, they, so to speak, may be laid hold of, and absorbed or digested by them.