xvi CONTENTS 



PAGE 



Note: ' Thermodynamical Observations on Chemical 

 Processes' 375 



Essay on ' Numbers and Measurements/ dedicated to 

 E. Zeller . 377 



PRESIDENT OF THE IMPERIAL PHYSICO-TECHNICAL INSTITUTE 



(REICHSANSTALT), CHARLOTTENBURG, 1888-1894 . . 379 



1888. 'On the Intrinsic Light of the Retina/ (Physical 

 Society) 381 



Correspondence with Heinrich Hertz .... 383 



1889. ' In memory of R. Clausius.' (Berlin Physical Society) 383 



Death of Bonders 384 



' On Atmospherjc_Mx3ynints.' (Berlin Academy) . . 385 

 ' On Atmospheric-Movements.' Second communication. 



(Berlin Academy, and Physical Society) .... 385 



Death of his son Robert 387 



Congress of Naturalists at Heidelberg .... 388 



1890. ' The Energy of the Waves and of the Wind.' (Berlin 

 Academy.) Wiedemanris Ann., XLI 390 



Representative of the University of Berlin at the Sex- 

 centennial Jubilee of the Foundation of the University of 

 Montpellier. 



'On the Work of the Imperial Physico -Technical 

 Institute* 391 



1891. ' Observations on Preparatory Training for Academical 

 Studies.' Discussions on Questions concerning Higher 

 Instruction, Berlin, Dec. 4-17 392 



' An Attempt to extend the Application of Fechner's Law 

 in the Colour System.' Zeitsch. f. Psycho!, u. Physio/, d. 

 Sinnesorgane, II 395 



'An Attempt to apply the Psycho-physical Law to the 

 Colour Differences of Trichromatic Eyes.' Zeitsch. f. 

 Psycho!, u. Physio!, d. Sinnesorgane, III . . . 396 



'Shortest Lines in the Colour System.' (Berlin 

 Academy) 397 



Celebration of his Seventieth Birthday on Nov. 2 . . 399 



1892. 'Autobiographical Notes. Address delivered at the 

 Banquet to celebrate his Seventieth Birthday.' (Berlin: 



A. Hirschwald) ......... 400 



'The Principle of Least Action in Electrodynamics.' 

 (Berlin Academy) 401 



