able to decompose the substrate peculiar to a particular organ. In a certain sense we give the serum a definite question to answer, when we add all kinds of organs to it, and observe which, or how many, of them are decomposed by it. If we find a decomposition, then we infer a somewhat abnormal activity of the cells of the corresponding organ. We presume that substances have been passed out, primarily from the cells of the organ in question, which have not vet been made sufficiently harmonious with the plasma, and that they still exhibit characteristic features peculiar to the cells in question.
In the future we shall undoubtedly avoid using whole organs and tissues for our researches, but shall select particular types of cells; and we shall have to be particularly careful in deciding, whether the tissue used is normal or modified. It is quite conceivable that, in certain diseases, only those tissues are decomposed which have been modified in a particular manner. In such a case the diseased tissue would be altered in such a way, that the substances that are out of harmony with the plasma would be more or less in disharmony with the cells of the normal organ; by which we mean, that compounds and decomposites would appear, which have completely disharmonious activities. And indeed, it would be possible to imagine that products would be formed that are out of harmony with the entire body,
