It is not very long since the current physiologic theories of vitality practically assumed that we knew all about it, or if we did not we soon should, as it was only a special manifestation of physical and chemical laws. Our knowledge of the subject has not contracted any since then, but we have learned facts that cause us to better appreciate its limits, to be a little less presumptuous in our ignorance, and to recognize that in the phenomena of life we have evidence of an agency not correlated with the ordinary forces of nature and not controlled by but controlling or guiding the ordinary recognized laws of matter.
A recently published paper (Nature, December 9) by Horace T. Brown and F. Escombe, recapitulates a number of facts already made known, but neglected, and adds some striking ones that are new and due to the investigations of these authors.