178 THe Microscope. 
Thus the micrococci and bacilli represent stages of develop- 
ment of the same organism. 
BACTERIA IN THE MILK OF ANIMALS INFECTED WITH CHARBON. 
The question has been raised whether the milk of a female 
in lactation affected with charbon contains the microbium of 
the infection. Recent experiments show conclusively that 
bacteria are tound in the milk of animals infected with charbon 
while they are still alive; but in much less numbers than in 
the blood. 
Mick0-ORGANISMS IN SorLs.—The superficial layers of the 
soil are rich in germs of bacteria, particularly in bacilli. Mi- 
crocoeci were only found in places which had not been cleansed 
from decaying matter. The quantity of micro-organisms di- 
minished very rapidly with increase of depth, and below one 
metre the soil is comparatively free from them. In one gramme 
of soil taken .20 metre from the surface it was estimated there 
were in each of three samples: 700,000, 870,000 and 900,000 
organisms. These organisms may have an important function 
in the transformation of substances to forms suitable to plant- 
food. 
BACTERIA ON THE SURFACE OF COINS.—Bacteria and algze have 
been found in great abundance in the incrustations and sedi- 
ments on silver and copper coins, especially old coins that have 
been in constant use for twenty or thirty years. 
Some of the sediment is placed in a drop of water and 
examined at once. Starch grains and various minute bodies 
are found. 
Two unicellular organisms are so constant that they are 
considered not as accidentally adherent substances but as or- 
ganisms which have their continual origin and seat in the in- 
crustations of coins in currency. The two new species are: 
chroococcus monetarum and pleurococcus monetarum. 
ACTION OF COLD ON MICROBES.—Various organisms, such as 
bacilli, when subjected to a temperature of 70° C. for 108 hours, 
and to 130 for 20 hours, are not destroyed; others, such as 
torula and the vaccine microbe, lost their power of producing 
fermentation. 
