88 EFFECT OF VARIED RESISTANCE PART i. 



three batteries passed through the tube, changes occurred 

 in the form and number of the strise corresponding 

 to the greater or less amount of the resistance offered 

 in the circuit. 



At the commencement of the experiments there were 

 18 inches of water in each of the tubes, which formed 

 the maximum resistance. The wires attached to the 

 terminal wires of the battery were placed inside of these 

 tubes, and as soon as they touched the surface of the 

 water a faint luminous discharge was seen at each ball 

 in the vacuum tube. As the wire attached to the nega- 

 tive end of the battery was slowly depressed, the two 

 luminous discharges appeared to travel towards or attract 

 each other, and at times a portion of the positive lumi- 

 nosity passed over and mingled with the negative ; in 

 this state the discharge was extinguished by a magnet. 



When the wire was pressed farther into the water a 

 dark space about an inch in length divided the light 

 into two parts, the positive glow being sharply defined, 

 the negative glow having an irregular edge. When the 

 wire had been about three inches deep in the water, the 

 positive and negative glows became more brilliant, and 

 a single clearly defined luminous disc burst from the 

 positive side and occupied the middle of the dark space. 

 When the wire was pressed down till 13 inches of it 

 were in the water, a second luminous disc travelled from 

 the positive side, and then the two luminous discs or 

 strise occupied the dark space at a little distance from 

 one another. As the wire was pressed more into the 

 water, three parallel luminous strise appeared, then four, 

 then five, and so on till as many as thirteen or fourteen 

 striped the dark central space. With the full power of 

 the battery, the adjacent disc impinged on the glow that 

 surrounded the negative ball. This disc was of a pale 

 green, those adjacent were reddish, while the negative 

 glow was of a bluish white; minute bright scintillations 



