836 The Philippine Journal of Science 1920 
solution of freshly slaked lime has a complete killing effect 
against Pseudomonas citri in 24 minutes, in the absence of 
organic compounds. Copper sulphate under identical conditions 
required a 0.5 per cent solution to kill Pseudomonas citri en- 
tirely in 24 minutes. 
TABLE 11.—Results of exposures with 3-day-old culture of Pseudomonas 
citri dilutions of a solution of commercial quicklime in water. Stock 
lime solution, 4 pounds to 50 gallons water. 
[Date of test, August 18, 1920; date of observation, August 16, 1920.] 
Dilution expressed in percentage. 
Exposure, 
10. | -20;. |. 90.. | @..1 BO.) OO. TO. | SO. | - oO. fF 100. 
Min. sec. 
2%|/—{/—,/—-}—-],-d=];/-J-)-]1- 
650} —|—}—]—]-]—]|-—-}—-|]-4 = 
7390} —-|—-}]—-/}/—-;/—-{/-|-!|]-|]-|]- 
0 0/ —}|—|—-}]—-!|—-;}]—-/-;-}-]|- 
wzwesl—}—/—-}-—-}—-]—-/-—-];-1|-|f- 
~o0/—}—{/—-}—-J—t}—-f—-|-i-j|- 
4 Exposure tested on potato, August 16; negative, August 18. 
This test was repeated with more dilute solutions of lime, 
and the results are shown in Table 12. 
TABLE 12.—Results of exposures, with 3-day-old culture of Pseudomonas 
citri in dilutions of a solution of commercial quicklime in water. 
[Date of test, September 3, 1920; date of observation, September 6, 1920.] 
Dilution expressed in percentage.* 
Ex 
0.01 | 0.02 | 0.03 | 0.04 | 0.05 | 0.06 | 0.07 | 0.08 | 0.09 | 0.10 
Min. see. 
2 30} + eo “8 = =e: + ms of ~ ate 
5 0; + + + + ma - + ae ~ mr 
Trt + + - i “+ — err —_ ~~ 
* 10 00} -+ > a ean ~ se sd = = 
12 30] + + +: _ a = a ~~ = es 
15 00; + + + os = | —_ | oon ie | aes ps 
" Percentages express the weight of quicklime in volume of water. 
A number of tests with Burgundy mixture * were also made. 
Burgundy 3-38-50 mixture, in which sodium carbonate is very 
slightly in excess of the amount necessary to precipitate the 
* Burgundy mixture is prepared by precipitating the copper from a 
copper sulphate solution with sodium carbonate. 
