﻿42 The Philippine Journal of Science 1914 



added 0.1 cubic centimeter of a 33^ per cent glucose solution. 

 These tubes were then placed in the autoclave and sterilized. 

 Ten cubic centimeters of normal defibrinated blood from a 

 susceptible animal were then added to each tube, which was 

 immediately inoculated with 0.5 cubic centimeter of defibrinated 

 blood from an animal suffering with rinderpest. Each culture 

 was then covered with from 1.5 to 2 cubic centimeters of sterile 

 paraffin oil, and was placed in the incubator at 40° C. 



In making transfers, a sterile pipette of 1 cubic centimeter 

 capacity was inserted into the medium from which the transfers 

 were to be made and the culture was agitated by filling the 

 pipette with medium and emptying several times. Either 0.3 

 or 0.5 cubic centimeter of the culture was transferred into the 

 blood-glucose tubes, which were then sealed with sterile paraffin 

 oil and placed in the incubator. 



I have found it best to make transfers every three or four 

 days as the virus in culture media has a tendency to lose its 

 virulence or die after remaining several days in one tube. 



In one series in salt-peptone mixture the virus in the primary 

 tube of culture medium lost its virulence on the sixth day, while 

 I was able to carry the same strain alive through four transfers, 

 covering a period of thirteen days. 



During the months of July, August, and September, 1913, 

 I have twice succeeded in carrying the virus in virulent form 

 in the glucose-blood medium to the sixth transfer, covering 

 periods of nineteen and twenty-one days, respectively. I have 

 twice succeeded in carrying the virus in virulent form in the 

 salt-peptone mixture to the fourth transfer covering periods of 

 twelve and thirteen days, respectively. 



In one series the fifth transfer from glucose blood medium 

 was carried into the salt-peptone mixture which was allowed 

 to incubate three days and proved virulent when injected into 

 a susceptible animal. These six transfers in culture media 

 cover a period of eighteen days after the virus was taken from 

 the infected animal. 



The question then arose whether there was really a multiplica- 

 tion of the virus in these media or whether the original blood 

 was transferred from one tube to another up to the sixth transfer 

 in sufficient quantity to cause the disease when injected into a 

 susceptible animal. In one of the series in which the sixth 

 transfer proved virulent, 0.3 cubic centimeter of the culture was 

 used in making the transfer each time. In computing the dilu- 

 tion of the original virulent blood in the sixth transfer, it was 



