Annual report of the Board of Control of the New York Agricultural Experiment Station . §00000000 J- u . t^- O !>• t^- i-4 H Fh Errc ft, OI PlPE Weightsamples. c^cocNioqco^oqooi gOOOOOOOO soooooooo & 108 Report of the Department of Bacteriology of the oft g H(NHNiO(NMH HHHHHHCOCOH O 9 H HHINHH N^OOHOOOOHNOCOHrtrtlMH <N t-H 2 oiO o CO O CD o CDft O w„ o OSCO 3 H^cOHHONOOOOOOOOOOOtDOOOOOO^COO w CDCO O r-i New York Agricultural Experiment Station. 109 tains very few bacteria and the precise count makes little there are many bacteria present in the smear it is often impossiblet
Annual report of the Board of Control of the New York Agricultural Experiment Station . §00000000 J- u . t^- O !>• t^- i-4 H Fh Errc ft, OI PlPE Weightsamples. c^cocNioqco^oqooi gOOOOOOOO soooooooo & 108 Report of the Department of Bacteriology of the oft g H(NHNiO(NMH HHHHHHCOCOH O 9 H HHINHH N^OOHOOOOHNOCOHrtrtlMH <N t-H 2 oiO o CO O CD o CDft O w„ o OSCO 3 H^cOHHONOOOOOOOOOOOtDOOOOOO^COO w CDCO O r-i New York Agricultural Experiment Station. 109 tains very few bacteria and the precise count makes little there are many bacteria present in the smear it is often impossibleto count the whole field of the microscope, owing to confusion causedby lack of guide lines. An eye-piece micrometer, ruled in squares,overcomes this difficulty. Here, too, it is not necessary to count alarge number of fields, for it is soon seen that the milk is of poorquality. Uneven distribution.— A more real source of error than the agree-ment or lack of agreement between duplicate counts is the unevendistribution of bacteria in the smear. It is evident that for accu-. Benton Hand Tally Register. rate quantitative work several fields must be counted to overcomethis error. This is a laborious operation if large numbers of bac-teria are present. Fortunately practical experience has shown thataccurate counts are not necessary in order to form a satisfactoryidea of the amount of bacterial growth which has taken place in agiven sample of milk. Counting is much more easily done if a handtally register is used. This can be procured from hardware dealers. Counting of the whole field.— Another error which becomesimportant in some cases lies in attempting to count the wholemicroscopic field. The margin of the microscopic field is invariablyso hazy as to obscure the bacteria lying in this region. This erroris not serious, however, where few organisms are present, but becomes 110 Keport of the Department of Bacteriology of the serious in the case of fields containing large numb
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectagriculture, bookyear
