186 ACTIVE IMMUNIZATION 



"In preparing the emulsion with which to inject patients it is 

 better to use the main room, and have a table with a drawer in which 

 are labels, glass rods, curved scissors, and forceps, the glass rods 

 having been wrapped in paper and sterilized in hot air. Erlenmeyer 

 flasks, 100 c.c. capacity, with cotton plugs, contain water, sterilized 

 in the autoclave. There are also stout wine-glasses covered with 

 paper caps and sterilized in hot air; the wine-glass inside does not 

 taper to a point, but has a flat bottom 2 cm. in diameter, which 

 corresponds to the diameter of the glass rods, which are 25 cm. 

 long; the wine-glass brimful holds 40 c.c. There is, of course, a 

 Bunsen burner on the table. 



"For the newly arrived patient the cord of the thirteenth and 

 fourteenth day is used; that is, a cord that has been drying over 

 caustic potash for thirteen and fourteen days. Such a cord measures 

 transversely J cm. The cord is for one instant passed into the Bunsen 

 flame, then with curved scissors, previously heated to redness in 

 the flame and allowed to cool, less than a millimeter, is transversely 

 cut from the end of the cord and allowed to drop into the wine- 

 glass; ten such pieces measure 8 mm. and weigh 20 mgm. This is 

 triturated with the glass rod until it has become thoroughly broken 

 or mashed according as it is recent or old. Then a few drops of 

 water are added and it is triturated until a milky fluid results, then 

 more water added until finally 15 c.c. is reached. 



"The emulsion now looks like rice water, and a sediment soon 

 accumulates; the paper cap is put back on the wine-glass, and 

 on the bottom rim, upper surface, is put a label with No. 14 on 

 it, meaning a cord that has dried fourteen days (older cords, 15-day 

 cords, are rejected and the bottle cleaned). The caustic potash, 

 after twice using, requires renewal; in twenty-eight days it looks 

 like wet white candy. The glass rods wear smooth and require 

 to have pieces cut with a file and broken off, thus becoming sharp 

 again. Similar to the above, the thirteenth-day cord is prepared 

 in a wine-glass. These wine-glasses are put in an agate-ware tray 

 or baking pan in which are placed pieces of filter paper, and a bowl 

 with some 3 per cent, solution of carbolic acid and two Pravaz 

 syringes. A list is made out with the names of the patients and the 

 age of the cords that is, the number of days they have been drying, 

 and the day of the month corresponding, which is the date on the 

 bottle, and the dose, e. g.: 



