THE INDIVIDUAL GROUPS OF PROTEINS 487 



(3) Oliver s Method. 



A series of standard test colours (a) circular in shape and graduated from 

 lo-ioo per cent, of haemoglobin and prepared against a Lovibond's tintometer 

 are arranged in a series on a frame. A capillary pfpette (c) attached to a small 

 handle is filled with blood from the finger. By means of a pipette (d) the blood 

 is washed from the capillary into a small circular cell (<?). The cell is nearly 

 filled with water and the blood and water are mixed with the handle of the 

 capillary pipette. The cell is covered with a cover glass ; a bubble should 

 form to show that the cell is not filled too full. The cell is matched against 

 the series of standards, the exact matching being ascertained with a camera 



tube. 



FIG. 60. 

 Artificial light should be used. If the colour does not match any 



tune Artinciai ii^ni MIUUIU -"- ^^^^.. . - 



standard exactly, the nearest lower standard is adjusted by adding to ,, tlnn 

 discs until the match is perfect. These d.scs are also graduated. 



