112 WYMAN, ON THE FORMATION OF INFUSORIA. 
ensured. When cold, the flasks are sealed at 4, figs. 1 and 2, 
with the blowpipe. 
In experiments 29 and 30, a glass tube filled with asbestos 
and platinum sponge was used instead of the iron tube filled 
with wires. 
The time during which the infusions were boiled varied, as 
will be seen by the records, from fifteen minutes to two 
hours, and the amount of infusion used from one twentieth 
to one thirtieth of the whole capacity of the flask, the object 
being to have the materials exposed to as large a quantity of 
air as possible. 
In the account which follows, especial mention is made, in 
most instances, of the time of the formation of the “ film.” 
This is always the first indication which can be had, without 
opening the flasks, that minute organisms are developed ; it 
is in fact made up entirely of them, as has been proved by 
repeated examinations with the microscope. It may first be 
detected in small patches, but soon covers the entire surface, 
and if the flask is gently moved so as to cause the infusion 
to change its position, the film adheres to the glass and is 
left by the liquid. In a few of the experiments no such film 
was formed. 
After the flasks were prepared, they were suspended from 
the walls of a sitting room near the ceiling, where they were 
exposed to a temperature of between 70° and 80° Fahr. 
throughout the day and nearly the same during the night. 
Experiment 1.* (1)+ Feb. 3rd, 1862. A few grains each 
of sugar, gelatine and fine cut hay were introduced into a 
flask of 500 c.c. capacity, 20 c.c. of water were added, and 
the whole thoroughly boiled. A film formed on the surface 
of the fluid on the eighth day, the flask was opened on the 
ninth, and found to contain large numbers of Bacteriums. 
Exp. 2. (1) Feb. 3rd. This was prepared in the same way 
as the preceding, excepting that pepper was added to the solu- 
tion. The flask was opened on the twenty-ninth day and 
Bacteriums were found in great numbers. 
Exp. 8. (1) Feb. 4th. A few grains of cheese, sugar and 
gelatine were dissolved in 17 c.c. of water, filtered and boiled 
in a flask of 500 c.c. capacity. A film formed on the nine- 
teenth day, the flask was opened on the thirty-sixth, and 
found to contain Bacteriums. 
Exp. 4. (1) Feb. 4th. Twelve cubic centimetres of a solu- 
* Tn the first seven experiments the time which the contents were boiled 
is not stated, but it was in no instances less than fifteen minutes. 
+ The figures in brackets following the number of the experiment indicate 
which of the three modes of preparing the experiment was made use of. 
