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matter which subsided was collected in a small stoppered 
bottle, and on the 13th of this month Dr. Smith requested 
me to examine the matter contained in this water. An 
illness prevented me from giving it so much attention as I 
could have wished. 
The water containing this air- washing was first examined 
with a power of 50 diameters only, for the purpose of getting 
a general knowledge of its contents ; afterwards magnifying 
powers varying from 120 to 1,600 diameters were employed. 
During the first observations, few living organisms were 
noticed ; but, as it afterwards proved, the germs of plant 
and animal life (probably in a dormant condition) were 
present. 
I will now endeavour to describe the objects found in 
this matter, and begin in the order in which they appeared 
most abundant. 
1st. Fungoid Matter . — Spores or sporidiae appeared in 
numbers, and, to ascertain as nearly as possible the numeri- 
cal proportion of these minute bodies in a single drop of 
the fluid, the contents of the bottle were well shaken, and 
then one drop was taken up with a pipette ; this was spread 
out by compression to a circle \ an inch in diameter. A 
magnifying power was then employed, which gave a field 
of view of an area exactly 100th of an inch in diameter, and 
it was found that more than 100 spores were contained in 
this space ; consequently the average number of spores in a 
single drop would be 250,000. These spores varied from 
10,000th to 50,000th of an inch in diameter. ‘ The peculiar 
molecular motion in the spores was observable for a short 
time, until they settled on to the bottom of the glass plate ; 
they then became motionless. 
The Mycelium of these minute fungi were similar to that 
of rust or mildew (as it is commonly named), such as is 
found on straw or decaying vegetation. 
When the bottle had remained for 36 hours in a room at 
