IOO 



Journal of Agricultural Research 



Vol. XX, No. 2 



Table XIII. — Comparative germicidal efficiency of chloramin T, Ddkin's solution, 

 eusol, and mercuric chlorid against Bacillus tuberculosis, with dilutions based on 

 available chlorin 



EXPERIMENT 24 



Disinfectant and dilution. 



Available 

 chlorin. 



Amount of serum. 



Guinea 

 pig No. 



Result. 



Autopsy. 



Chloramin T. . . . 



Do 



Eusol 



Do. . . . 

 Dakin's solution. 



Do . . 



Mercuric chlorid: 



1 to 500 



Do 



Tubercle bacillus 

 suspension. 



Do 



1 to 200 

 1 to 200 

 1 to 200 

 1 to 200 

 1 to 200 



1 to 200 



None. 

 25 per cent. 



None. 

 25 per cent. 



None. 



25 per cent. 



None. 



25 per cent. 



None. 



25 per cent. 



54549 

 5455o 

 54551 

 5455 2 

 54555 



54556 



54557 

 54558 

 54559 



5456o 



Died . . 



...do... 

 Killed** 

 Died . . 



...do... 



...do... 



Killed" 

 Died . . 

 ...do... 



...do... 



Typical lesions. 



Do. 



Do. 



Do. 

 Not tubercu- 

 lous. ° 

 Typical lesions. 



Normal. 

 Typical lesions. 

 Do. 



Do. 



EXPERIMENT 25 



Chloramin T. 



Do 



Eusol 



Do 



Dakin's solution. 



Do 



Mercuric chlorid: 



1 to 500 



Do 



Tubercle bacillus 

 suspension. 



Do 



1 to 200 

 1 to 200 

 1 to 300 



1 to 300 

 1 to 200 



1 to 200 



None. 



25 per cent. 



None. 



25 per cent. 

 None. 



25 per cent. 



None. 



25 per cent. 



None. 



25 per cent. 



Typical lesions. 

 Do. 



Not tubercu- 

 lous. 



Typical lesions. 



Not tubercu- 

 lous. d 



Typical lesions. 



Normal. 

 Typical lesions. 

 Do. 



Do. 



Killed after 10 weeks. 



& Died after 7 weeks of an intercurrent pneumonia. 



c Died after 2 months; no lesions observed; death probably due to scurvy. 



<* Died after 1 month of an intercurrent pneumonia. 



< Killed after 2 months; perfectly normal. 



The results of trie experiments upon the tubercle bacillus would seem 

 to indicate that the chlorin compounds are entirely inefficient so far as 

 that organism is concerned. These are the results to be expected in 

 view of the use of antiformin for isolating tubercle bacilli. 1 



CARBOLIC-ACID COEFFICIENTS OF THE CHLORIN ANTISEPTICS 

 The results here given are those of a large number of tests made by 

 the Rideal- Walker method (10), modified only as stated below. Aside 

 from the use of Staphylococcus aureus and Bacillus pyocyaneus as test 

 organisms in addition to B. typhosus, the only modifications were the 

 use of bacto-peptone instead of Witte's peptone and a relaxation of the 

 rule that coefficients are to be deduced only where there is life after 5 

 minutes and death after 7^2 minutes. 



On account of variation in the resistance of the cultures, especially 

 Staphylococcus aureus and Bacillus pyocyaneus , it was inconvenient to 



1 Amounts actually found inefficient were as follows: Chloramin T, i to so; eusol, 0.5 percent; and Dakin's 

 solution. 0.5 percent. 



