JOURNAL 



OF THE 



ASIATIC SOCIETY OF BENGAL. 



Part II.— PHYSICAL SCIENCE. 



No. I.— 1876. 



I — On tlie General Theory of Duplex Telegraphy . — 

 By Louis Schwendler. 

 (Continued from Vol. XLIV, Part II, 1875.) 

 III. The compensation method.* 

 This method is the oldest ; Fig. 3 gives the general diagram. 



FIG. 3». 



* Dr. "Wilhelm Gintl, Director General of Telegraphs in Austria, is the in- 

 ventor of this earliest method. In 1853 he made the first practical experiment on a line 

 between Vienna and Prague (240 miles). 



