. A text-book upon the pathogenic Bacteria and Protozoa for students of medicine and physicians. Bacteriology; Pathogenic bacteria; Protozoa. Determination of Bacteria in Water 239 Ice always contains bacteria if the water contained them before it was frozen. In Hudson River ice Prudden found an average of 398 colonies in a cubic centimeter. A sample of water when collected for examination should be placed in a clean sterile bottle or in a hermetically sealed pre-ster- ilized glass bulb, and must be examined as soon as possible, as the bacteria multiply rapidly in water which is allowed to sta
. A text-book upon the pathogenic Bacteria and Protozoa for students of medicine and physicians. Bacteriology; Pathogenic bacteria; Protozoa. Determination of Bacteria in Water 239 Ice always contains bacteria if the water contained them before it was frozen. In Hudson River ice Prudden found an average of 398 colonies in a cubic centimeter. A sample of water when collected for examination should be placed in a clean sterile bottle or in a hermetically sealed pre-ster- ilized glass bulb, and must be examined as soon as possible, as the bacteria multiply rapidly in water which is allowed to stand for a short time. If the water to be examined must be transported any considerable distance before the manipulations are performed, it should be packed in ice. The greatest care must always be exercised that the unnatural conditions arising from the bottling of the water, the changes of temperature, and the altered relationship to light and the atmosphere, do not modify the number of contained bacteria. 100. Fig. 85.—Frost's plate counter, for counting colonies of bacteria on Petri msh or plate cultures. The cross-lines divide the figure into square centimeters. The numbers at the top of the figure indicate the area in centimeters of the various discs. The area of each sector (a and b) is one-tenth of the whole area. The detection of such important bacteria as the colon, typhoid and dysentery bacilli, and the cholera spirillum, will be considered in the chapters treating of those respective organisms. Drinking-water, especially that furnished to large cities, is not infrequently contaminated with sewage, and contains intestinal bacteria—Bacillus coli. For the ready determination of this organ- ism, which is an important indication that the water is polluted. Smith* has made use of the fermentation-tube in addition to the * "Amer. Jour. Med. Sci.," 1895, ex, p. Please note that these images are extracted from scanned page images that may have been digitall
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Keywords: ., bookcentury1900, bookdecade1910, booksubjectbacteri, bookyear1916
