influence of heat than similar elements of less highly vitalized cold-blooded animals. Keeping these considerations in view, therefore, we may see by the following figures how harmonious are the facts already ascertained:
TEMPERATURES AT WHICH DEATH OCCURS.
| Simple aquatic organisms are | killed at | 104°-113° | Fahr. |
| (Spallanzani, Max Schultze, and Kühne.) | |||
| Tissue-elements of cold-blooded animal—Frog | "" | 104° | |
| (Kühne.) | |||
| Tissue-elements of warm-blooded animal—Man | "" | 111° | |
| (Strieker and Kühne.) | |||
| Tissue-elements of Plants Urtica, Tradescantia, and Vallisneria | "" | 116½°-118½° | |
| (Max Schultze and Kühne.) | |||
| Eggs, Fungus-spores, and Bacteria-germs | "" | 122°-140° | |
| (Spallanzani, Liebig, Tarnowski, and others.) | |||
So far as we can ascertain by really scientific methods, free from all obvious possibilities of misinterpretation, these are the temperatures which undoubtedly kill the different varieties of that common life-stuff known as Protoplasm—the "physical basis of life," as it has been termed by Prof. Huxley. That it should present this comparative unity in its behavior toward heat as weir as to other physical agencies, is surely not in antagonism with the most generally-approved biological doctrines, of which Prof. Huxley has made himself the most celebrated exponent in this country. In his own forcible language he tells us as follows: "Beast and fowl, reptile and fish, mollusk, worm, and polype, are all composed of structural units of the same character, namely, masses of protoplasm with a nucleus. . . . What has been said of the animal world is no less true of plants. . . . Protoplasm simple or nucleated is the formal basis of all life. . . . Thus it becomes clear that all living powers are cognate, and all living forms are fundamentally of one character."[1]
4. I now turn to say a very few words concerning the general attitude and specific statements made by those who, wishing not to give in their adherence to the fact of the occurrence of "spontaneous generation," affect to believe that Bacteria-germs or other kinds of living: matter can resist the influence of boiling water.
In the first place, it should be said that not one of these persons has striven to justify his position by scientific evidence bearing directly upon the death-point of Bacteria and their germs, while several of them have glaringly attempted to make good their position in the most unscientific manner, that is, by adducing experiments admitting of two interpretations as though they were instances only admitting of one, and then of these two possible interpretations selecting that
- ↑ "Lay Sermons," pp. 126-129.
