A summary of a lecture on matters connected with the life and health of the public / by J.T.C. Nash.

  • Nash, James Thomas Charles, 1865-
Date:
1901
Catalogue details

Licence: In copyright

Credit: A summary of a lecture on matters connected with the life and health of the public / by J.T.C. Nash. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    obliged, though reluctantly, to relinquish it. It must necessarily be so until the State and the people recognise the importance to them- selves of providing adequate funds for scientific research. Bacteria and the Preservation of Foods. It was in 1856 that Pasteur demonstrated that fermentation was bound up with the life and growth of living cells, the cells using a small percentage of the fermentescible material for the purposes of their own growth and nutrition ; while the larger proportion became fermented and transformed chiefly into alcohol and carbonic acid gas. The dependence open fermentation on living micro-organisms has been fully established. By the application of these scientific facts and principles we in these days can utilise preserved foods of various kinds. I cannot here enter into a full discussion of the rflle of bacteria in connection with industrial processes, but I may say that the products of the vital action of bacteria are of an importance in these processes which has not hitherto being sufficiently recognised. Un- aware of their agency as we have been, yet we have long been indebted to them. Take for instance, the process of “ retting ” in the “ Maceration industries.” The production of indigo depends on the fermentation set up by a special bacterium on the leaves of the indigo plant. The “ sweating ” of hides and the “ curing ” of tobacco are other processes which might be mentioned as depending on the action of bacteria. What a lesson as to the value of co-operation ! These minute microscopic plants, so small that millions of them could pass side by side through the eye of a needle, so insignificant individually, achieving so great results when co-operating in count- less millions. Soil bacteria form a subject of great interest and importance to agriculturalists. Three very important economic groups of bacteria are found in the interstices of soil. 1. Denitrifying bacteria, which break down nitrates. 2. Nitrifying bacteria, which oxidise ammonia and nitrites into nitrates. 3. Nitrogen-fixing bacteria.