70 SELLARDS AND SHAKLEE. 



presence of phenolplithalein. The solutions were titrated within four days after 

 sterilization. In two separate lots of solutions, the variations from this mean 

 of 3 per cent were only slight. This amount of change is not greatly in excess 

 of the conversion which takes place in the corresponding unheated solutions. 



This solution was subsequently tested upon three typical cases in 

 collapse and all recovered. The response from collapse was quite similar 

 to that obtained with ordinary physiological saline solution. These 

 three patients were sporadic cases occurring late in the cholera season, 

 and for this reason they are not included in the group which is reported 

 later. 



Another factor was introduced in that some of the severest cases 

 also received an anticholera serum. The reports concerning antichol 

 era sera indicate on the whole that there is a certain minimal benefit 

 to be derived from its use. (9) 10) H) Its effect on the death rate is 

 not sufficiently great to constitute any conclusive evidence of its value. 

 Furthennore, if the use of alkalies affects only those cases which die 

 in ursemia (15 per cent), then its influence on the death rate would 

 not be very pronounced. By utilizing both methods of treatment it 

 was thought that the combined effect might be great enough to show 

 itself. 



Aside from its having antitoxic properties, the serum perhaps might 

 be of some minor value in protecting the corpuscles and the proteins 

 of the blood from the action of the alkali; also it might aid in the 

 retention of the injected fluid Avithin the blood vessels, especially if 

 the exudation of fluid through the vessel walls is dependent upon vital 

 as well as physical phenomena. 



The serum ■w^as prepared in a manner somewhat similar to that followed by 

 Schurupoff. (10) Ten strains of cholera vibrios were tested and no marked dif- 

 ferences were formd in the minimal lethal dose of the killed cultures upon 

 intraperitoneal injection into guinea pigs. The cultures were killed by adding 

 sodium hydroxide to a thick emulsion of cholera vibrios in physiological saline 

 solution. 



Only freshly isolated strains of cholera were employed for the preparation of 



the serum, a new strain being obtained every month. The growth from 15 to 



20 large agar slants was used for each injection, the slants each measuring about 



3 by 8 centimeters. This growth was suspended in 20 to 30 cubic centimeters 



of salt solution and for the first injection the vibrios were killed by the addition 



N 

 of 2 cubic centimeters of — sodium hydroxide. Upon the addition of the alkali, 



the suspension changed from a limpid, opaque emulsion to a viscous, translucent 

 solution. The viscosity was so great that dilution with an equal volume of 

 salt solution was usually required in order to effect a thorough mixing. Further 

 addition of the hydroxide diminished the viscosity of the fluid and apparently 

 rendered it less toxic. The amount of sodium hydroxide was gradually decreased, 

 until toward the end of the period of immunization, only one-fourth of original 

 amount was used. This was not sufficient to kill the emulsion of vibrios, but 

 their virulence for gninea pigs was diminished. 



