The number and distribution of micro-organisms in the air of the Boston City Hospital : with some carbonic acid determinations / by Greenleaf R. Tucker.

  • Tucker, Greenleaf R.
Date:
[1889]
Catalogue details

Licence: Public Domain Mark

Credit: The number and distribution of micro-organisms in the air of the Boston City Hospital : with some carbonic acid determinations / by Greenleaf R. Tucker. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    1883 162 STATE BOARD OF HEALTH. [Jan. the sick demand. On Monday, Tuesday, Thursday and Saturday of each week, friends of patients are admitted from two to three p.m., usually to the number of two to three hundred, and distribute themselves throughout the various wards, the number of visitors in each ward being often equal to the number of patients ; this afforded oppor- tunity to observe the effect upon the air of increased numbers of people, over those habitually present. It was found nec- essary to limit the number of experiments each day to five, including the outside air. The total number of wards being eighteen, four or five days elapsed before a return could be made to a given point; and the entire month was necessary to accumulate sufficient data for each ward, from which to draw conclusions. During December, samples were taken mornings, gen- erally between eight and ten o'clock, the wards at that time being in a more or less disturbed condition, — beds are made, floors swept, surgical dressings changed, and the general comfort of the patients attended to. By following this plan, two series of results were obtained, showing the condition of the air under quiet and disturbing influences. The month of January and part of February were devoted to special investigation, which the previous work had shown to be necessary. Methods employed in the Quantitative Determination of Micro-organisms in the Air. The introduction by Koch in 1881 of a solid-culture me- dium for the study of micro-organisms has resulted in methods by which we can determine with facility, and approximately, if not with accuracy, the number of micro-organisms in the air. Koch himself exposed plates coated with a solid nutri- ent gelatine, upon which aerial microbes settled, and could be counted after development. Hesse, however, was the first to apply this principle quantitatively to investigations of the air, and in 1883 published the well-known method bearing his name. Petrie, in Germany, and Frankland, in England, have proposed methods, which, while retaining the solid-culture medium of Koch, differ essentially from the method of Hesse and from each other, in detail. In this ARMLD FORCES MEDICAL LIBRARY WASHINGTON, D. C. ^