CONTENTS ix 



PAGE 



1853. ' Report on Work done in Acoustics in 1848.' Fortschr. 

 d. Physik. 



'On the Scientific Researches of Goethe. 1 (Lecture at 

 Konigsberg.) (Trans.) Helmholtz, Pop. Sci. Led., Series I 103 



' On a Hitherto Unknown Alteration in the Human Eye 

 during Accommodation.* Berl Monatsber. . . . 107 



First Journey to England ...... 109 



1854. ' Reply to the Observations of Dr. Clausius.' Poggend. 

 Annal, XCI 115 



' On the Interaction of Natural Forces.* Lecture, 

 (trans.) Phil. Mag. [4], XI ; Pop. Set. Lect., Series I . .120 



'On the Rate of Certain Processes in Muscle and Nerve.* 

 Berl. Monatsber. 125 



1855. ' On the Composition of Spectral Colours.* Poggend. 

 Annal.,XCIV 131 



1 On the Sensibility of the Human Retina to the Most 

 Refrangible Rays of Solar Light.* Poggend. Annal., XCIV 133 



'Addendum to a Paper by E. Esselbach on the Measure- 

 ment of the Wave-Length of Ultra-Violet Light.* Berl 

 Monatsber. 134 



' On the Accommodation of the Eye.* Graefe's Archiv 

 fur Ophthalmologie 134 



' On Human Vision.* (Konigsberg, Lecture) . . . 138 



First meeting with W. Thomson (Lord Kelvin) . . 145 

 PROFESSOR OF PHYSIOLOGY AND ANATOMY AT BONN, 1855-1858 147 



1856. 'On the Movements of the Thorax.* (Bonn, Nieder- 



Rheinische Gesellschaft) 148 



~V Contraction -Curves of Frogs* Muscles.* Nieder-Rh. 

 Sitzungsber. ......... 149 



^ On the Explanation of Lustre.* Nieder-Rh. Sitzungsber. 149 



' On Combination Tones.* Poggend. Anna!., XCIX . 151 

 -^The Action of the Muscles of the Arm.* (Lecture, Bonn) 

 ' The Telestereoscope.* Pogg. Annal. 

 Textbook of Physiological Optics. Parti . . .155 



1857. ' On the Vowel-Tones.* Letter to Bonders . . 158 



1858. ' On Integrals of the Hydrodynamic Equations which 

 express Vortex-Motions.' Crelle's Journ. t LV, (trans.) Phil. 

 Mag. [4], XXXIII 167 



' Sur le Mouvement le plus general d*un Fluide.* ' Sur 

 le Mouvement des Fluides.' ' Reponse a la Note de 

 M. J. Bertrand du 19 Octobre 1868* 170 



