A manual of hygiene and sanitation.

  • Egbert, Seneca, 1863-1939.
Date:
1900
Catalogue details

Licence: Public Domain Mark

Credit: A manual of hygiene and sanitation. Source: Wellcome Collection.

Provider: This material has been provided by the Harvey Cushing/John Hay Whitney Medical Library at Yale University, through the Medical Heritage Library. The original may be consulted at the Harvey Cushing/John Hay Whitney Medical Library at Yale University.

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    being benefactors rather than otherwise to the human race. The function of the saprophytic organisms is to break up dead organic matter into simpler chemical compounds and ultimately into end-products, such as carbonic acid, ammonia, and water, these latter substances being once more utilized in the nutrition of the higher forms of vege- table life, which are, in turn, necessary to the existence of animal life upon the globe. Indeed, it is only when the student of hygiene fairly realizes the great scope of the functions of these minute but almost omnipresent scavengers that he can comprehend the important part they play in the purification of our environment. In the air they possibly help the oxygen to destroy the harmful effluvia and exhalations of men and animals and the float- ing debris of organic substances; in the soil, the common receptacle of the wastes and refuse of vital activity, they quickly and continually convert these noxious additions into foods of the highest value to growing plants; in running streams and quiet pools they are of the greatest importance in the removal of the dangerous impurities washed from the surface of the land or recklessly dis- charged from human habitations, factories, and the like. And not only do the saprophytes help mankind in this way, but members of the class are beneficent in many others. For example, they enable those plants, the legu- minosa?, which yield us the largest supply of vegetable proteids, to derive much of their nitrogen almost directly from the atmosphere; they have much to do with the flavor and value of dairy products, and new uses in which they may be employed in the domestic or commer- cial affairs of life are being announced from day to day. Thus we find this class of the bacteria, which comprises