423 



diminis"hed fhe number of bacteria, au addition of 10 per cent of salt, 

 was not sufficient to comiiletely destroy all of the germs. 



Samples of artificial butter were examined according- to tlie same 

 methods used for natural butter. The number of germinating- organ- 

 isms found in 1 gram of the former was about 750,000, while the 

 smallest number noticed in natural butter was 2,405,555. It is stated 

 further that the appearance of the plate cultures of artificial butter in 

 general was very different from those of natural butter. The forms 

 found in the artificial butter were molds, sprouting fungi, and a bac- 

 terium not further described. The effect of cold and of common salt 

 on the germs in artificial butter was tested in the same manner as with 

 natural butter, and the results were found to agree with those obtained 

 for natural butter, the addition of salt up to 13 i^er cent and exposure 

 to a temperature of — 9° 0. for 14 days being insufficient to destroy 

 all the germs. 



The author announces the above investigations as merely the begin- 

 ning of work which he proposes in these lines. 



The behavior of bacteria of typhoid fever, tuberculosis, and 

 cholera in butter, H. Laser {Zeitsch. f. Hygiene, 10, pp. 513-530). — 

 The author refers to the investigations of Heim,* who studied the abihty 

 of certain pathogenic bacteria to live in butter. His experiments went 

 to show that cholera germs sown in poor butter sh'ghtly sour lost their 

 vitality in a few days, but in butter of the best quality they retained 

 their vitahty for over a month. Typhoid fever and tuberculosis germs 

 were found active after remaining in butter the former for 3 and the 

 latter for 4 weeks. Gasperini recognized virulent tuberculosis bacilli 

 among germs which had been in butter for 120 days. 



Laser arrived at different conclusions from Heim with regard to the 

 length of time the germs of these diseases are capable of living in 

 butter. He mixed tuberculosis and typhoid fever bacilli and cholera 

 spirilli each in butter and in the fat and casein separated from butter 

 by heating, and made daily examinations of duplicate plate cultures of 

 each material. Colonies of typhoid fever bacilh ceased to be developed 

 on any of the plates after the sixth day, and there was a steady decrease 

 in the number of colonies each day from the first. Cholera bacteria 

 could not be recognized in either the butter or the casein after 5 days, 

 and those in the fat had disappeared by the fourth day. Heim's experi- 

 ments were carefully duplicated in another series of experiments, but 

 typhoid fever bacilh from fat ceased to develop colonies on the fifth, 

 and those from casein or butter on the seventh day. 



The vitality of the tuberculosis germs was tested by inoculating guinea 

 pigs. After the germs had been in butter for 6 days their number 

 had diminished, but they still retained their vitality. After 12 days, 

 however, all the bacilli capable of life or infection had disai)peared. 



«Axb. a. d. Kais. Ges. Amte, vol. 5. 



