8 Transactions of the Society. 



It is manifest then, that if a fluid be put in the bulb and stand 

 at the level of the dotted line A, it will fill and be in communica- 

 tion with the cell 0. 



E is a hollow bulb filled with calcined air, and hermetically 

 sealed ; but it does not communicate with the bulb A on account 

 of the presence of a thin glass partition or septum F. The object 

 of this is, that when, by boihng, the air has been driven out of the 

 bulb A, and the whole interior space has been hermetically sealed 

 at J, air may be again introduced, which is accomplished thus : H 

 is a pointed piece of platinum wire, heavy enough by a sharp shake 

 to break the septum F, but too large in diameter to pass through 

 the neck G, but of course the calcined air immediately enters and 

 restores to the fluid its normal conditions. 



Fig. 5 is precisely the same as the above, the same letters 

 referring to the same parts in both ; but it has an addition to it 



/^ Fig. 5. 



marked M N. This is a tube opening at N into the bulb A, but 

 until needed the communication of the tube with the interior of the 

 bulb is prevented by the thin partition L. The object of this is, 

 that supposing a given infusion to have become sterilized in relation 

 to a certain organism, by any ascertained temperature, to determine 

 whether nevertheless the fluid is still capable of sustaining the 

 organism if it be reintroduced. To do this, a piece of platinum 

 wire, as before, is taken and touched with a fluid in which the 

 living organism abounds ; it is then placed in the tube K. The 

 tube is then sealed at M ; the piece of platinum is shaken sharply, 

 breaks the septum L, and falls into the fluid, inoculating it. 



The first matter to be determined, and this with accuracy, is 

 the death-point, by heat endured in a fluid, of the adult organism. 

 This was tested in succession for the whole six organisms, but to 

 make the method of doing this quite plain, it will be enough to 

 give the manipulative details in one case, and state the results in 

 the others. I select for this purpose the monad which I call for 

 working purposes the Uniflagellate, the life-history of which is given 



