Isolation 281 



For staining the meningococcus the method of Pick and 

 Jacobsohn * is highly praised by Carl Frankel, who modifies 

 it by adding three times as much carbol-fuchsin as is recom- 

 mended in the original instructions, which are as follows : Mix 

 20 c.c. of water with 8 drops of saturated methylene-blue 

 solution ; then add 45-50 drops of carbol-fuchsin. Allow 

 the fluid to act upon the cover-glass for five minutes. The 

 cocci alone are blue, all else red. 



Isolation. The organism can be secured for cultivation 

 either from the purulent matter of the exudate found at 

 autopsy, or from the fluid obtained by lumbar puncture. To 

 obtain this fluid Park f gives the following directions: "The 

 patient should lie on the right side with the knees drawn up 

 and the left shoulder depressed. The skin of the patient's 

 back, the hands of the operator, and the large antitoxin 

 syringe should be sterile. The needle should be 4 cm. in 

 length, with a diameter of i mm. for children, and larger for 

 adults. The puncture is generally made between the third 

 and fourth lumbar vertebrae. The thumb of the left hand 

 is pressed between the spinous processes, and the point of 

 the needle is entered about i cm. to the right of the median 

 line and on a level with the thumb-nail, and directed slightly 

 upward and inward toward the median line. At a depth of 

 3 or 4 cm. in children and 7 or 8 cm. in adults the needle 

 enters the subarachnoid space, and the fluids flow out in 

 drops or in a stream. If the needle meets a bony obstruc- 

 tion, withdraw and thrust again rather than make lateral 

 movements. Any blood obscures microscopic examination. 

 The fluid is allowed to drop into sterile test-tubes or vials 

 with sterile stoppers. From 5 to 15 c.c. should be with- 

 drawn. No ill effects have been observed from the opera- 

 tion." 



In making a culture from this fluid Park points out that, 

 as many of its contained cocci are dead, a considerable 

 quantity of the fluid (say about i c.c.) must be used. 



The cocci have also been cultivated from the nasal dis- 

 charges in the six cases studied by Weichselbaum and in 

 eighteen studied by Scherer. To determine the presence of 

 the coccus in the nasal discharges where other similar cocci 

 may be present, Gram's stain may be used and followed by 



* " Berliner klin. Wochenschrift," 1896, S. 811. 



t " Bacteriology in Medicine and Surgery," Philadelphia, 1899, 

 p. 520. 



