Rotary spark-gap, [28]

Selenium, [99]

cells, [8], [34], [55], [60], [64], [109], [110]

machines, [45]

Self-induction, [24], [78]

Sensitiveness of selenium cells, [113]

ratio of, [113]

Silvered quartz threads, [44], [46]

Spark-gap, [27]

Speed regulator, [68]