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.

110. Apparent Diffraction Really Due to STINE Penumbral Shadows.

110_a_. Non-diffraction. PERRIN

159_a_. Non-Refraction

111. Source of X-rays Tested by SCRIBNER and Interceptance of Assumed Rectilinear M’BERTY Rays from the Cathode.

112. Source of X-rays on the Inner Surface SCRIBNER and of the Glass Tube Determined by M’BERTY, Pin-hole Images. PERRIN

112_a_. Anode Thought to be the Source. Cause DE HEEN of Error Suggested.

113. Pin-hole Pictures by X-rays Compared LODGE with Pin-hole Images by Light to Determine the Source. X-rays Most Powerful when the Anode is the Part Struck by the Cathode Rays.

114. Valuable Points Concerning Electrical LODGE Apparatus Employed.

115. X-rays Equally Strong during Fatigue of LODGE Glass by Phosphorescence.

116. Area Struck by Cathode Rays Only an ROWLAND, Efficient Source when Positively CARMICHAEL, Electrified. and BRIGGS

117. Transposition of Phosphorescent Spot SALVIONI, and of Cathode Rays without a Magnet. ELSTER, GEITEL, and TESLA

117_a_. Molecular Sciagraphs in a Vacuum Tube. HAMMER and FLEMING