* * * * *

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ILLUSTRATIONS

FIG. PAGE

1. Diagram showing effects of capacity on an intermittent current 5

2. Bernochi's wireless apparatus 7

3. Knudsen's wireless apparatus 10

4. Wireless transmitting station 13

5. Diagram of experiment illustrating principle of line photograph 16

6. Drawing of transmitting machine 17

7. Drawing of transmitting machine 18

8. Drawing of stylus 18

9. Electrical connections of machine 19

10. Photograph of Author's experimental machine _Frontispiece_

10a. End view of Author's experimental machine }
} _facing page_ 21
10b. View of image broken up by a "cross" screen}

11. Connections of complete transmitting apparatus 23

12. Drawing of ordinary type of spark-gap 27

13. Synchronous rotating spark-gap 28

14. Non-synchronous rotating spark-gap 28

15. Connections for complete wireless photographic station 30

16. Connections of Professor Korn's apparatus 31

17. Connections of Poulsen's photographic recorder 33

18. Author's photographic receiver 38

19. Enlarged drawing of cone 39

20. End view of Author's photographic receiver 39

21. Connections of decohering apparatus 41

22. Connections for complete photographic receiver 42

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23. Arrangement of Einthoven galvanometer 45

24. Einthoven galvanometer arranged for receiving 46

25. Connection of telephone relay 49

26. Drawing of Author's improved photographic receiver 51

27. Diagram giving ratio of vibrating arm 51

28. Arrangement of