402 APPENDIX. 



— in two or three days, if we employ one of the boxes used by 

 Mr. Tyndall — it has been proved that any organic infusions 

 whatever may be preserved in the case without undergoing the 

 least putrefactive change, and without producing bacteria. 



On the other hand, bacteria will swarm in similar infusions, 

 after an interval of from two to four days, if the vessels which 

 contain them are exposed to the air by which the cases are 

 surrounded. Mr. Tyndall can drop into his boxes, at any time 

 he wishes, some blood from a vein or an artery of an animal, 

 and show conclusively that such blood will not, under these 

 circumstances, undergo any putrefactive change, 



Mr. Tyndall concludes his work with a consideration of the 

 probable application of the results given in his paper to the 

 etiology of contagious diseases. We share his views on this 

 subject entirely, and w^e are obliged to him for having recalled 

 to mind the following statement from our Studies on the Silkicorm 

 Disease : — " Man has it in his power to cause parasitic diseases 

 to disappear off the surface of the globe, if, as we firmly believe, 

 the doctrine of spontaneous generation is a chimera." 



THE END. 



