American Red cross textbook on elementary hygiene and home care of the sick / by Jane A. Delano and Isabel McIsaac.

  • Delano, Jane A., 1862-1919.
Date:
1913
Catalogue details

Licence: In copyright

Credit: American Red cross textbook on elementary hygiene and home care of the sick / by Jane A. Delano and Isabel McIsaac. Source: Wellcome Collection.

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    individual to whom the medical sciences owe more than they do to Pasteur * * * Pasteur died in 1895. Until 1882 the methods of study and observation of bacteria were so imperfect that only geniuses like Pasteur and Koch were able to make use of the new science, but as a result of a series of experi- ments by Koch and others, the uncertainties were largely removed and bacteriology placed upon a practical working basis which has revolutionized the whole practice of medicine, of agriculture and of many industries. The difficulty which beset the early investigators of bacteria was the presence of numberless kinds of germs together and the impos- sibility of separating a single species for observa- tion. Bacteria were first grown artificially in beef bouillon, known as the culture medium, but the great number of kinds and the fluid medium effec- tually blocked the way to observation, until Robert Koch found that the addition of gelatin was not unfavorable to bacterial growth and would produce a solid transparent broth. Meanwhile it was found that to secure pure cultures of a single species all utensils, media or anything coming in contact with them must be freed of bacteria, i. e., the articles must be sterilized or the cultures would not be pure. Later the discovery was made that by the use of aniline dyes the different kinds could