embarrassed to explain how the toad could live in its singular prison and how it became shut up there. The strangest ideas have been expressed on this point. The ridiculous hypothesis has even been proposed of an imperceptible toad-germ that was developed in the interior of the stone. The fact of the survival of the toad, despite the impenetrability of the stone, becomes less doubtful when we recollect the similar experiments on animals inclosed in plaster, which we have mentioned above. But the problem of the toad's introduction into the stone still remains unsolved.
M. Charles Richet had occasion to study this question some months ago, and came to the conclusion that the fact was real, observing that even if, in the actual condition of science, certain phenomena were still inexplicable, we were not warranted in denying their existence, for new discoveries might at any time furnish an explanation of them. "The true may sometimes not be probable." But science takes accounting of the truth, not of the probability.
Hibernating mammalia are capable of putting on all the appearance of death. The marmot, during its lethargic sleep, is cold, the temperature of its body being hardly 1° C. above that without. It respires only three times a minute; and the beatings of the heart, which rise to ninety a minute in the active life of the animal, fall to ten in a minute. Bats, during the cold season, hang like dead bodies. One may take them in his hands, press them, and throw them into the air, without their manifesting any sign of feeling.—Translated for the Popular Science Monthly from La Monde de la Science et de l'Industrie.
| SKETCH OF ROBERT KOCH. |
ONE of the most eminent of the colaborers of Pasteur in the investigation of the relations of microorganisms to disease-infection, and one whose labors have been most fully appreciated by intelligent men, is Dr. Robert Koch, of Berlin. He was born at Clausthal on the 11th of December, 1843, the son of a high officer in the department of mines. He attended the gymnasium in his native town, and afterward—from 1862 to 1866—studied medicine at Göttingen. He became an assistant in the Allgemeine Krankenhaus, or General Hospital, at Hamburg; began the practice of medicine in 1866 at Langenhagen in Hanover; then settled at Racknitz, in Posen. From 1872 till 1880 he was physikus or district physician at Wallstein, in the district of Bomst. He engaged in studies of bacteriological diseases, including wound-
