99_A_ Briefs Regarding Action between SCHUSTER, to Electric Charge and Light. RIGHI, 99_T_. STOLSTOW, BRANLY, BORGMANN, MEBIUS, _et al._ CHAPTER IX. 100. Stereoscopic Sciagraphs. THOMSON, E. 101. Obtaining Manifold Sciagraphs THOMSON, E. Simultaneously upon Superposed Photographic Films and through Opaque Materials, and thus Indicating Relative Sensitiveness of Different Films to X-rays. Intensifying Process Applicable in Sciagraphy. Thick Films Appropriate. 101_a_. Sciagraph Produced through 150 Sheets LUMIÈRE. of Photographic Paper. 102. Discharge Tube Adapted for Both THOMSON, E., Unidirectional and Alternating and SWINTON Currents. 103. X-rays. Opalescence and Diffusion. THOMSON, E., PUPIN, and LAFAY 103_a_. Diffusion and Reflection in Relation to IMBERT, _et Polish. al._ 104. Fluorometer. Fluorescing Power of THOMSON, E. Different Discharge Tubes Compared. 105. Modified Sciascope for Locating the THOMSON, E. Source and Direction of X-rays. Phosphorescence Not an Essential Accompaniment in Production of X-rays. 106. X-rays from Discharge Tube Excited by RICE, PUPIN, Wimshurst Machine. Full Details Given and MORTON of the Electrical Features. 107. Source of X-rays Determined by RICE Projection through a Small Hole upon Fluorescent Screen Adjustable to Different Positions. 107_a_. Use of Stops in Sciagraphy. LEEDS and STOKES 107_b_. X-rays from Two Phosphorescent Spots. MACFARLANE, KLINK, WEBB, CLARK, JONES, and MORTON 108. Source of X-rays Determined by Shadows STINE of Short Tubes. 109. Instructions Concerning Electrical STINE Apparatus for Generating X-rays.