246 SEC. 9. MAGNETISM. 



1138. Apparatus for the demonstration of Magnetic 



Friction, constructed by the late Mr. Kleemann in Halle. 



Prof. Dr. Dove, Berlin. 



V. APPARATUS FOR INVESTIGATIONS CONNECTED 

 WITH DIAMAGNETISM. 



1139. Glass Tubes prepared by Faraday for testing the 

 magnetic and diamagnetic character of Gases. 



The Royal Institution of Great Britain. 



The tubes containing the gas to be examined were suspended in the mag- 

 netic field of a powerful magnet, the result being either attraction or repul- 

 sion of the tubes as the gases they contained were either magnetic or dia- 

 magnetic. Phil. Trans., 1850. 



1140. Bars of Borate of Lead Glass, made and used by 

 Faraday, for the action of magnets on polarized light. 



The Royal Institution of Great Britain. 

 Phil. Trans., 1845. 



1141. The Diamagnetic Box of Michael Faraday, con- 

 taining spheres, cubes, and bars of diamagnetic metals j tubes of 

 various liquids, bars of borate of lead, glass, various crystals, 

 cradles, supports, &c., used by Faraday in his researches on 

 diamagnetism. Professor Tyndall, F.R.S. 



1142. Instrument used in researches on the Polarity of 

 the Diamagnetic Force. Professor Tyndall, F.R.S. 



1143. Specimen of " Faraday's Heavy-glass." 



George Gore, F.R.S. 



1144. Electro-Magnet for Induction and Diamagnetic 



Experiments, made in 1850, of a broad plate of iron, so as to 

 obtain the largest possible inductive power from the conducting 

 wire. James P. Joule, D.C.L., F.R.S. 



The coil is composed of a bundle of copper wires, and has a resistance 

 about equal to that of a Daniell's cell, exposing a surface of one foot square. 



1144a. A large diamagnetic Apparatus, with glass case, 

 rods, &c. Warmbrunn, Quilitz, $ Co., Berlin. 



