Cultivation 699 



Spronck* believed that he had successfully cultivated the organ- 

 ism upon glycerinized, neutralized potatoes, first seeing the growth 

 after the lapse of ten days. Cultures thus prepared were found to 

 be agglutinated by the blood-serum of lepra cases, and he recom- 

 mended the agglutination test for the diagnosis of obscure cases of 

 the disease. 



Ducrey claimed to have cultivated the lepra bacillus in grape- 

 sugar, agar, and in bouillon in vacua. His results need confirmation. 



Rostf claimed to have isolated and cultivated the lepra bacillus 

 upon media free from sodium chlorid. The technic of his method 

 is thus described by Rudolph :{ 



" Small lumps of pumice stone are washed and then dried in the sun, and then 

 allowed to absorb a mixture of i ounce of meat extract and 2 ounces of water. 

 This pumice stone is then placed in wide-mouthed bottles and placed in the auto- 

 clave. Each bottle is provided with a stopper through which pass two tubes, the 

 one tube opening into the autoclave and reaching nearly to the bottom of the 

 bottle, and the other leading from the top of the bottle into a condenser adjoining. 

 When the cover of the autoclave is adjusted and the steam admitted, then in the 

 case of each bottle, the steam passes by the one tube to the bottom of the bottle, 

 and rising through the pieces of pumice stone, the steam, carrying with it the 

 volatile constituents of the meat-extract, reaches the condenser by the second 

 tube. The vapor in the condenser yields the salt-free nutrient medium in the 

 proportion of 2 liters to each ounce of meat-extract originally used. The medium 

 is collected from the condenser in sterilized Pasteur flasks which are kept plunged 

 during the process in a freezing mixture in order to condense some of the volatile 

 alkaloids from the beef that would otherwise escape. The nutrient fluid is now 

 inoculated with the bacillus of leprosy and the flasks kept at 37C. for from four 

 to six weeks; at the end of this period when examined the flasks should present a 

 turbid appearance with a stringy white deposit." 



Clegg announced the cultivation of lepra bacilli from human 

 leprous tissue in symbiosis with ameba and other bacteria. The 

 organisms thus cultured he kept alive in subcultures. The method 

 devised by Clegg was the starting-point of a more extended re- 

 search by Duval,|| who, after confirming the work of Clegg, found 

 that the bacillus could be cultivated directly from human lesions 

 upon culture-media containing tryptophan, without the symbiotic 

 ameba or other bacteria. The initial culture was somewhat difficult 

 to secure, but once the bacilli grew, transplantation was easily 

 and successfully carried on for indefinite generations. He further 

 found that the lepra bacillus could be successfully started to grow 

 upon the ordinary laboratory media if bits of leprous tissue were 

 placed upon them, and at the same time some symbiotic organism, 

 such as the colon, typhoid, proteus, or other bacilli, added. Or 

 if the tissue were already contaminated the lepra bacilli proceeded 

 to multiply. Duval interprets this to mean that the lepra bacillus 

 is unable to effect the destruction of the albumin molecule alone, and 



* "Weekblad van het Nederlandsch Tijdschrift voor geneeskunde," Deel n, 

 1898, No. 14; abstract "Centralbl. f. Bakt.," etc., 1899, xxv, p. 257. 

 t "Brit. Med. Jour.," Feb. 22, 1905, and "Indian Med. Gazette," 1905. 

 t "Medicine,", March, 1905, p. 175. 

 "Philippine Journal of Science," 1909, rv, 403. 

 1| "Journal of Experimental Medicine," 1910, xn, 649; 1911, xm, 365. 



