Ill 



this end a series of test tubes plugged with cotton were 

 thoroughly sterilized by baking. Then into each test 

 tube was poured a certain amount of distilled water. 

 To the water in each tube was then added variable 

 amounts of electrozone. For example, the hrst tube 

 contained lo cubic centimeters (about 250 drops) of 

 water and i drop of electrozone ; the second tube, 25 

 cubic centimeters (625 drops) of water and i drop of 

 electrozone , the third, 30 cubic centimeters (750 drops) 

 of water and i drop of electrozone ; the next two each 

 contained 50 cubic centimeters (1,250 drops) of water 

 with I drop of electrozone ; and the last two each 100 

 cubic centimeters (2,500 drops) of water and i drop 

 of electrozone. Into each test tube was then dropped 

 a large fly (upon whose body the fungus rapidly grows). 

 Each fly had previously been thoroughly rubbed upon 

 the fungus-covered body of one of the trout brought 

 from the creek the day before. The test tubes were 

 then left for twenty-four hours, at the end of which time 

 the fungus growth could be seen upon the bodies of all 

 of the flies except those in the tubes containing 10 cubic 

 centimeters of water with i drop of electrozone and 

 25 cubic centimeters of water with i drop of electro- 

 zone. At the end of forty-eight hours the fungus had 

 developed in the second of these tubes. The outcome 

 of these experiments is, then, that to prevent the growth 

 of the fungus the ratio of electrozone to water must be 

 I drop of the former to 250 drops ( 10 cubic centimeters) 

 of the latter. It is to be regretted that other tubes 

 containing i drop of electrozone to 15 cubic centime- 

 ters (375 drops) of water and i drop of electrozone to 

 20 cubic centimeters (500 drops) of water were not pre- 

 pared, for it seems quite probable that further tests will 

 show that a smaller amount than one part of electro- 

 zone to 250 parts of water will suffice. However, with- 

 out waiting to learn the outcome of such experiments 

 it seems best, the case being so urgent, to proceed at 



