One kind of conclusion only is to be drawn from these experiments, the conditions of which were in every way similar, except as regards the degree of heat to which the inoculated fluids were subjected--seeing that the organisms were contained in a fluid, which had been proved to be eminently suitable for their growth and multiplication.[37] If inoculated fluids which have been raised to 122° and 131° F. for ten minutes, are found in the course of a few days to become turbid, then, obviously, the organisms cannot have been killed by such exposure; whilst, if similar fluids, similarly inoculated, which have been raised to temperatures of 140°, 149°, 158°, and 167° F. remain sterile, such sterility can only be explained by the supposition that the organisms have been killed by exposure to these temperatures. [33] It was necessary to boil the solution first, in order to destroy any living things or dead ferments which it might contain. It must contain one or the other, because an unboiled solution of this kind, in a corked bottle about half full, will always become turbid; whilst, after it has been boiled, it may be kept indefinitely under similar conditions without becoming turbid. [34] The proportion was one drop of the fluid, opaque with organisms, to an ounce of the clear solution. [35] Into which a piece of glass tube had been slipped to prevent collapse. [36] Allowing even five minutes for the temperature of the 1 oz. of fluid to become equal to that of the bath, it would then have remained exposed to this amount of heat for about ten minutes. [37] Fluids which had remained sterile would always, in the course of thirty-six or forty-eight hours after inoculation with living _Bacteria_, become more or less turbid. Some of these experiments have been repeated several times with the same results. On three occasions, I have found the fluid speedily become turbid, which had only been exposed to 131° F. for ten minutes, whilst on three other occasions I have found the inoculated fluid remain clear, after it had been exposed to a heat of 140° F. for ten minutes.[38]