158 THE AMERICAN MONTHLY [May 



Inks. Dr. Marpmaiin of Lcipzi''-, h;is recently j^ublished 

 the results of the microscopical examination of (>7 samples 

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

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

 cocci. Nig-rosin ink, taken from a freshly opened bottle, 

 was found to contain both saprophytes and bacteria. Red 

 and blue inks also yielded numerous ])acteria. 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 i>ottle 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- 

 gfists. Since time out of memory it has ])een a well-known 

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

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

 vestigation and found that iish 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 suljihu- 

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

 with deep 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 investig-ators. The microbiolog^ists 

 finally took the matter in hand and a recent observer now 

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

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

 bottom. This microbe decomposes mineral sulpTiates and 

 has been named Bacillus hydrosulfuricus ])()inicus. 



One more indictment is added to tiie many ag-uinst the 

 house-tly. Yersin communicated plag'ue to g-uinea-i)ig;s by 

 the inoculation of sterilized water in which flies found dead 

 in the laboratory had been rubbed up. 



