ESTIMATION OF HEMOGLOBIN 



143 



plaster mirror below, 5, figure 122, which casts light through the opening. 

 Beneath the plate is a metal framework containing a colored glass wedge, 

 and along the side of the same is a scale graduated so as to indicate the 

 percentage of hemoglobin corresponding to the shades of the different parts 

 of the wedge. This frame- ^ a r 



work can be moved by the 

 wheel T which fits into a rack 

 on its lower surface. The 

 scale can be read through a 

 small opening M in the plate. 

 Into the large circular open- 

 ing of the plate fits a cylin- 

 drical metal cell G with a glass 

 bottom and divided by a metal 

 partition into two equal parts. 

 One of these halves lies over 

 the wedge and is filled with 

 distilled water. The other 

 contains the solution of blood 



in which the hemoglobin is 



j ,-,, FIG. 122. Fleischl's Hemoglobinometer. 



to be estimated. The appar- 

 atus is usually supplied with three cells. Of these, the first two are 

 used in estimating the hemoglobin according to Miescher. This is the 

 method now generally used. These cells are furnished with a glass cover 

 having a groove whicn fits upon the partition of the cell. Over this cover 

 is placed a diaphragm with a longitudinal slit, which only permits of 

 the central part of each side of the cell being seen. 



The patient's ear or finger is pricked, and the blood from the wound 

 sucked up into the graduated pipet until it reaches the mark J, , or -f, a 

 i per cent, solution of sodium carbonate is then sucked in until the upper 

 mark is reached. The pipet is then well shaken in order to mix the blood 

 thoroughly. One-half of each of the two cells, which are, respectively, 12 

 and 15 millimeters high, is then filled with the mixture, the other half 

 being filled with water. An important point is that the liquids should com- 

 pletely fill the cells. The cover-glasses and diaphragms are then applied 

 , and the cells are ready for examination. This must be done by artificial 

 light. Moreover, in order to have accurate results, light of the same inten- 

 sity should be always used. One of the cells is placed on the plate and the 

 wheel T turned until the colors of the two halves exactly correspond. When 

 this point is reached, the result is read off on the scale through the opening 

 M. This should be repeated several times with each of the cells, and the 

 average of the readings taken. The result obtained with the 1 2-millimeter 



