THE GERM OF LIFE.

Thames Guardian and Mining Record, Volume I, Issue 148, 30 March 1872, Page 3

THE GERM OF LIFE.

The following interesting paper was read by Dr Grace Cal vert at the British Association meeting, at Edinburgh : —lt has hitherto been assumed by the advocates of the theory of spontaneous generation that a temperature of 212 deg. Faiir., or the boiling point of the fluid operated on, was sufficient to destroy all protoplasmic life. To determine this point experiments ■were made with solution of gelatine, and water that had been in contact with putrid meat. To carry out these experiments, the author prepared a series of small tubes, made of very thick well annealed glass, each tube about four centimetres in length, and having a bore of five millimetres. The fluid to be operated upon was introduced into them, and left exposed to the atmosphere a sufficient length of time for the germ of life to be largely developed. Each tube was then hermetically sealed, and wrapped in wire guaze. They were then placed in an oil bath, and gradually heated to the required temperature, at which they were maintained for hnlf-an-hour. The sugar solution was prepared by dissolving one part of sugar and ten parts of common water, and then exposed to the atmosphere all night, so that life may impregnate it, then placed in tubes and allowed to stand five days. Some of the tubes were kept without being heated, others heated to 200, 300, 400, and 500 degrees Fahr. respectively. After being kept twenty-four days the contents of the tubes were microscopically examined. In the solution not heated much life was seen, at 212 deg. a great portion of the life had disappeared, at 300 deg. the sugar was slightly charred but the life not entirely destroyed, whilst at 400 and 500 degrees the sugar was almost entirely charred, and no trace of life observed. A small black vibrio observed, resists the high temperature and all chemical solutions. The hay infusion was made by macerating hay in common water for an hour, filtering the liquor, and leaving it exposed to the atmosphere all night, when it was sealed in the small tubeß, The results were examined twenty

four days after being hcatsd— In this case as in the sugar solution, tifo was observed in tho solutions heated to two hundred and three hundred degrees Fahr. while in thoss heated to 400 deg. and oOOdcg. Fahr. life was destroyed. In the solution not heated, fungus matter was observed, while none appeared in any of the heated solutions. A solution of gelatine, of such strength that it remained liquid in cooling, was exposed to the atmosphere for twenty-four hours, and introduced into the small tubes, which wsre sealed and heated. The fluids were examined twenty-four days after being heated. The auimalculae in this case were principally of a different class from those observed in the two preceding cases, and this class were injured at 100 deg. Fahr.; at 212 deg. a considerable diminution in the amount had taken place ; whilst at 300 deg. all life was destroyed. Water was placed in an open vessel, and a piece of meat suspended in it became putrid. The fluid placed, in the usual tubes, heated and the contents examined after twenty-four days ; in this case life was still observed at 300 deg. Fahr., whilst at 400 deg. it had disappeared. Parts of the putrid meat solution that had been heated were mixed with albumen to ascertain whether it still retained the power of propogating life, the result being that up to 300 deg. Fahr. life and its germs had not been destroyed, whilst at 300 they had. Putrid meat liquor was exposed for four and twenty hours to a temperatuie ranging from the freezing point to 17 min. below that point. Immediately after melting the ice, the animalculae appeared languid and their power of locomotion was greatly decreased, but in two hours they appeared as energetic as before.