238 THE ACUTE PNEUMONIAS 



freed of surface contamination by washing in sterile saline. The mouse 

 may die in from five to twenty-four hours, and if the peritoneal exudate 

 contains a strong and fairly pure growth of the pneumococcus the abdo- 

 minal cavity is washed out with 5 -c.c. saline, cultures being at the same 

 • time made in broth and on blood-agar plates. The peritoneal washings are 

 first centrifuged slowly to precipitate gross material, and the supernatant 

 fluid is then centrifuged at a high speed to precipitate the bacteria. The 

 bacterial deposit is emulsified in saline to form a fairly heavy suspension 

 which is used for a macroscopic sedimentation test. If the pneumocoeci 

 in blood cultures or in other exudates are to be employed, emulsions may 

 be obtained by similar procedures. A bacterial emulsion being prepared, 

 0'5 c.c. of Serum I. (1-20), - 5 c.c. of Serum II. (undiluted), - 5 c.c. of 

 Serum II. (1-20), and 0-5 c.c. of Serum III. 1 (1-5) are placed in four 

 tabes, and 0'5 c.c. bacterial emulsion added to each, and in a fifth tube a 

 mixture of 0"1 e.c. sterile ox bile and 0'4 c.c. bacterial emulsion is made 

 up ; the series is placed in a water bath at 37° C. for one hour, and the 

 result read off. Sedimentation in any one of the four tubes indicates that 

 the strain belongs to the type by the serum of which it is agglutinated : 

 if no reaction occurs in any of the tubes, and the organism is soluble in 

 bile, it belongs to Type IV. 



The Treatment of Pneumonia with Anti-sera. — Many years 

 ago the Klemperers treated a certain number of cases of human 

 pneumonia by serum derived from immune animals, apparently 

 with a certain measure of success, and more recently Rb'mer 

 issued through Merck a polyvalent serum prepared by immunis- 

 ing different species of animals with growths of the pneumococcus 

 on sheep-serum glycerine bouillon and mixing their sera. The 

 results obtained, though in some cases satisfactory, were irregular, 

 and the subject was illuminated by Neufeld and Haendel, who 

 insisted that in the use of any anti-pneumococcic serum means 

 should be taken for ensuring that it had an antagonistic action on 

 the particular strain present in the particular infection treated. 



Evidence confirming this view has been obtained in the New 

 York investigations on pneumonia, in which the determination 

 of the different types of the pneumococcus was followed by an 

 estimate of the therapeutic capacities of the anti-sera prepared 

 against Types I., II., III. (v. supra). It was found that while 

 the anti-serum to Type I. had a marked curative effect on cases 

 of pneumonia due to the Type I. pneumococcus, the anti-sera to 

 Types II. and III. had practically no effect on cases attributable 

 to these types ; furthermore the anti-serum to Type I. had little 

 or no effect on cases caused by Types II. and IIL These facts 

 throw light on the irregular and generally disappointing result 

 obtained hitherto with the ordinary polyvalent antipneumococcal 



1 There is apparently sometimes difficulty in effecting the agglutination of 

 Type III. on account of the consistence of its capsule, and special methods may 

 be necessary ; seeHanes, Jmirn. Exp. Med., 1914, xix. 38. 



