158 THE AMERICAN MONTHLY [May 



Inks. — Dr. Marpmann of Leipzig", has recently published 

 the results of the microscopical examination of 67 samples 

 of ink used in schools. Most of these inks were made with 

 g"all-nuts, and contained saprophytes, bacteria and micro- 

 cocci. NigTosin ink, taken from a freshly opened bottle, 

 was found to contain both saprophytes and bacteria. Red 

 and blue inks also yielded numerous bacteria. In two 

 instances Dr. Marpmann succeeded in cultivating- from 

 nig-rosin ink a bacillus which proved fatal to mice within 

 four days. This ink had stood in an open bottle for three 

 months, and the inference drawn from the inquiry is that 

 ink used in schools should be kept covered when not in 

 use. 



A Water Microbe. — One of the unaccountable phenom- 

 ena of the Black Sea has been explained by the bacteriolo- 

 g-ists. Since time out of memory it has been a well-known 

 fact that there were no deep-sea fish in the body of water 

 mentioned. Away back in 1850 the scientists made an in- 

 vestig-ation and found that fish could not live at a g-reater 

 depth than 200 fathoms in the water of the Black Sea on 

 account of the presence of a superabundance of sulphu- 

 retted hydrog-en. Time and ag-ain the waters were stocked 

 with depp sea fish, but all died on account of the poisonous 

 g-as which was g-enerated in such quantities in those por- 

 tions of the water which should have been their natural 

 habitat. It was known that the g-as was at the bottom of 

 all the trouble, but exactly where the g-as came from was 

 what so puzzled the investigators. The microbiologists 

 finally took the matter in hand and a recent observer now 

 announces that the gas is g-enerated by the countless num- 

 ber of microbes which make their home in the ooze at the 

 bottom. This microbe decomposes mineral sulphates and 

 has been named Bacillus hydrosulfuricus ponticus. 



One more indictment is added to the many ag-ainst the 

 house-fly. Yersin communicated plag-ue to guinea-pigs by 

 the inoculation of sterilized water in which flies found dead 

 in the laboratory had been rubbed up. 



