PUTREFACTION AND INFECTION. 73 



platinum wire. The copper wires passed through the 

 case, and were connected with a voltaic battery outside. 

 The spiral was heated by the current from this bat- 

 tery. After a few minutes' heating ebullition set in, 

 and was continued for five minutes in each tube. Two 

 other tubes containing tlie same infusions were boiled 

 in the same way, and afterwards hung outside the case 

 containing the two protected tubes. 



In another chamber were placed two tubes con- 

 taining infusions of beef and mutton. The arrange- 

 ment and the treatment were precisely the same as 

 those just described in the case of hay and turnip. 



Examined some months subsequently, the exposed 

 tubes of all four infusions were found turbid and 

 covered with Penicilliuni, while all the four protected 

 tubes remained unchanged. During the boiling process 

 some floccLili detached themselves from the tinned sur- 

 faces of the copper wires ; but in the protected tubes 

 these have fallen to the bottom, and left the supernatant 

 liquid clear. Platinum wires would have been better 

 than tinned copper ones. 



§ 15. Partial Discussion of the Results. 



Thus by experiments, reiterated in many cases, 

 with urine, mutton, beef, pork, hay, turnip, tea, coffee, 

 hops, haddock, sole, salmon, codfish, turbot, mullet, 

 herring, eel, oyster, whiting, liver, kidney, hare, rabbit, 

 fowl, pheasant, grouse, has the induction been established, 

 that the power of developing Bacterial life by atmospheric 

 air and its power of scattering light, go hand in hand. 

 "We shall immediately examine more closely what this 

 means. 



The necessity of employing strong infusions has 

 been frequently dwelt upon, if we would realize the 



