and Laboratory Methods. 2539 



rice paper moistened with 80 per cent, alcohol and thoroughly dried. The 

 staining is with iron haematoxylin and a saturated solution of bismarck brown in 

 00 per cent, alcohol. H. w. c. 



Rosenau. The Bacteriological Impurities of The use of gl3'cerine in the preparation 

 Vaccine Virus. Bui. 12 Public Health and ^f vaccine virus has been widelv her- 

 Marine Hospital service, 1903. 



aided as a means of reducing or destroy- 

 ing the bacteria in the virus so as to prevent the unfortunate cases of tetanus, 

 blood poisoning, etc., which occasionally follow vaccination. Much interest has 

 therefore attached to the question of the presence of bacteria in vaccine and the 

 value of glycerine in destroying them. Rosenau has made a long series of 

 bacteriological examinations of virus to answer these questions. His method 

 consists in placing the virus in a measured quantity of sterile bouillon, agitating 

 until all clumps were thoroughly broken up. The dry points were first softened 

 in a small quantity of bouillon and then rubbed clean in bouillon with proper 

 precautions. The glycerinated virus from capillary tubes was also mixed with 

 bouillon and the capillary tube washed clean. Especial care was necessary to 

 insure the breaking up of the clumps. From the bouillon mixture agar plates 

 were made in which a definite number of drops of the bouillon was mixed. The 

 plates were incubated at 37° and after growth an estimation of the total number 

 of bacteria in each dry point or glycerine tube was easily obtained. The result 

 of the work in brief is to show that no form of virus is free from bacteria 

 although the glycerineated virus is purer than the ordinary dry points. 



H. \V. C. 



Muller. Ueber das Wachstum und die Leben- The interest that has developed in 



statigkeit von Bakterien, sowie den Ablauf ^^^^^^ ^ concerning fermentative 



fermentativer Processe bei niederer lempe- ^ ° 



ratur unter spezieller Berucksichtigung der changes at low temperatures, especially 



Fleisches als Nahrungsmittel. Arch. f. Hyg., ; reference to ripening of cheese, makes 

 XLvir, p. 127, 1903. ^ ° ' 



this investigation of Muller of particular 



interest. Most of the work reported has been carried on at a temperature of 

 exactly 0° C. For maintaining such a temperature the author devises an appa- 

 ratus with three chambers inside of each other. The material to be tested is 

 placed in the inner one and the other two are filled with ice. The ice in the outer 

 chamber is changed as it melts, while that in the middle chamber melts very 

 slowly and needs little change. A thermometer shows that a constant tempera- 

 ture of freezing is easily maintained for a long time. With such a device he 

 tests the growth of several bacteria and the fermentative power of several enzymes. 

 His general conclusion is that bacteria grow readily enough at freezing, but, of 

 course, much more slowly than at higher temperatures. The fermentative action 

 of enzymes also continues actively at these temperatures. The author also tests 

 the action of temperatures below freezing. These lower temperatures, however, he 

 is not able to control so closely, and the results are not so exact. He finds that 

 bacteria do not grow at temperatures below freezing. The curing or ripening 

 of flesh, which is known to go on at low temperatures, even below freezing, 

 Muller regards as due chiefly to the enzymes present rather than to the action of 

 bacteria. h. w, c. 



