A manual of practical hygiene / by Edmund A. Parkes ; edited by F.S.B. Francois de Chaumont.

Date:
1878
Catalogue details

Licence: Public Domain Mark

Credit: A manual of practical hygiene / by Edmund A. Parkes ; edited by F.S.B. Francois de Chaumont. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    pass into the alimentary canal, and it is even more probable tbat this should be the case with all except the lightest and most finely divided substances, than that they shoidd pass into the lungs. Although incapable of present proof, there is some reason to think that some of the specific poisons, which float about in an impure atmosphere, such as those which arise from the typhoid or cholera evacuations, may produce their first effects, not on the lungs or blood, but on the alimentary mucous membrane, with which they are brought into contact when swallowed. Sub-Section L'—Suspended Matters. Nature of Suspended Substances.—An immense number of substances, organic and inorganic, may be suspended in the atmosphere. From sod the winds lift sdica, finely powdered sdicate of alumina, carbonate and phosphate of calcium, and peroxide of iron. Volcanoes throw up fine particles of carbon sand and dried mud, which passing into the higher regions, may be carried over hundreds of miles. The animal kingdom is represented by the debris of the perished creatures who have lived in the atmosphere, and also it woidd appear that the ascen- sional force of evaporation will lift even animals of some magnitude from the surface of marsh water. The germs, also, of Vibriones, Bacteria, and Monads (rtwe may call these animals), are largely present, and small eggs of various From the vegetable world pass up seeds and debris of vegetation : pollen spores of fungi mycoderms, mucedines, which may grow in the atmosphere! and innumerable volatde substances or odours. y ' r}l?m thVffa tlle.7ind s™ and the chl0lide of sodium becoming diied is so diffused through the atmosphere, that it is difficult, on spectrum analysis, to find a spectrum without the yeUow line of soda muche,ra£iand hfabitations1of man> however, furnish matters probably of much greater importance m a hygienic point of view It is not easy at present to give a complete enumeration of all the sub- stances but the following are the chief facts, divided under the he^«4 of suspended substances in the external air; in rooms inhabited bTSdthv persons; m rooms inhabited by sick persons; in workshops and factorfi. 7 Suspended Substances in External Air. 1 Dust and sand showers. In different parts of Europe there occur from mmmmm species of diatoms V * 5 ?TeS'n f icmA *» led monsoon ,],nwL w , ese sand-storms are sometimes vchm7ZZ^ZTmZ rCl m™ltl,atouy Ti0lent3tora °f » /aserts, and ^X^See'T 8^ ™tes> - ft™ * ^ t Comptes Renrtus, 1872, avid, p. 991.