. Essentials of laboratory diagnosis; designed for students and practitioners. hment in its place opposite this. The candle should beso adjusted that its upper end is flush with the top of the claspwhich holds it. See that the pipette, composed of the rectan-gular glass plates, is thoroughly cleansed and dry. The spacebetween the plates is filled by applying the edge of the pipetteto the side of a fairly large drop of blood. Adjust this pipettein its place and rotate the color scale, by means of the milledscrew, until the colors match. Hold the instrument steady to 56 THE BLOOD. prevent any fl
. Essentials of laboratory diagnosis; designed for students and practitioners. hment in its place opposite this. The candle should beso adjusted that its upper end is flush with the top of the claspwhich holds it. See that the pipette, composed of the rectan-gular glass plates, is thoroughly cleansed and dry. The spacebetween the plates is filled by applying the edge of the pipetteto the side of a fairly large drop of blood. Adjust this pipettein its place and rotate the color scale, by means of the milledscrew, until the colors match. Hold the instrument steady to 56 THE BLOOD. prevent any flickering of the flame. No dark room is necessary,but it is advisable to point the instrument at some dark objectand to avoid direct sunlight, as the shadings of color are notso easily matched by direct day light. As soon as the colors arematched make the readings. This reading is observed on theleft side of the case in the small open space,—the line whichcoincides with the beveled edge of the opening represents thepercentage of hemoglobin, on the basis of a value of Fig. 12.—Dares Hemoglobinoheter. grams of hemoglobin per 100 cubic centimeters as 100 per is, therefore, easy to calculate the direct amount of hemo-globin in the blood examination. This instrument has the advantages that undiluted bloodis used, that the scale of comparison is usually very accuratelystandardized, that it is convenient, easy of manipulation, andrapid in giving results. Coagulation of the blood does not occursufficiently soon to introduce an error, providing the reading istaken within a reasonable time. It is more convenient for gen-eral use than most others, can be used in a light room, but itis rather expensive, and an occasional inaccurate instrumenthas been found. ENUMERATION OF THE CORPUSCLES. 57 ENUMERATION OF THE CORPUSCLES. Method of Thoma-Zeiss.—The Thoma-Zeiss apparatus con-sifits of a counting slide and two diluting pipettes, termedmelangeurs (Fig. 13). This slide is so
Size: 1345px × 1858px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1910, bookpublisheretcetc, bookyear191
