33. Forcing Effect of the Striæ at a SOLOMONS Perforated Diaphragm. CHAPTER III. 34. Electric Images. RIESS 35. Electrographs on Photographic Plate by SANFORD and Discharge. MCKAY 36. Positive and Negative Dust Pictures LICHTENBERG upon Lines Drawn by Electrodes. 36_a_. Photo-electric Dust Figures. HAMMER 36_b_. Dust Portrait. HAMMER 37. Electrical Images by Discharge KARSTEN Developed by Condensed Moisture. 37_a_. MAGNETOGRAPHS. MCKAY 38. Bas-relief Facsimiles by Electric PILTCHIKOFF Discharge. 39. Distillation of Liquids by Discharge. GERNEZ 40. Striæ. Black Prints on Walls of Tube. DE LA RUE and MÜLLER CHAPTER IV. 41. Discharge Tube in Primary Current. GASSIOT Striæ. Least E. M. F. Required. 42. Current Interrupted Inside of Discharge POGGENDORFF Tube instead of Outside. 43. Source of Striæ at the Anode. Color DE LA RUE and Changed by Change of Current. MÜLLER 44. Dark Bands by Small Discharges SOLOMONS Disappear on Increase of Current, and Appear Again by Further Increase. 45. Motion of Striæ. Method of Obtaining SPOTTISWOODE Motion when Desired and of Stopping the Same. 46. Motion of Striæ Checked at the Cathode. THOMSON, J. J. Tube, 50 ft. Long. The Anode the Starting-point. 47. Electrolysis in Discharge Tube. THOMSON, J. J. 48. Heat Striæ without Luminous Striæ. DE LA RUE and MÜLLER 49. Sensitive State. Method of Obtaining. SPOTTISWOODE Telephone Used to Prove and MOULTON Intermissions. 49_a_. Cause of Sensitive State Detected by SPOTTISWOODE Telephone. and MOULTON 50. Sensitive State Illustrated by a REITLINGER and Flexible Conductor within the URBANITZKY Discharge Tube. 51. System of Operating Discharge Tubes. TESLA Excessively High Potential and Enormous Frequency. 52. Discharge-tube Phenomena by MOORE Self-induced Currents. CHAPTER V. 53. Dark Space around the Cathode. CROOKES