APPENDIX. 



467 



" What object, then, can be offered to us more worthy of contempla- 

 tion than the attributes of this intermedium between ourselves and the 

 outer world ? 



" Its existence, the modes of motion through it, its transverse vibra- 

 tions, their creation of the ideas of light and colors in the mind, the in- 

 terferences of its waves, polarization, the conception of radiations and 

 their physical and chemical effects these have occupied the thoughts of 

 men of the highest order. The observational powers of science have 

 been greatly extended through the consequent invention of those grand 

 instruments, the telescope, the microscope, the spectrometer. Through 

 these we have obtained more majestic views of the nature of the uni- 

 verse. Through these we are able to contemplate the structure and 

 genesis of other systems of worlds, and are gathering information as to 

 the chemical constitution and history of the stars. 



" In this noble advancement of science you, through some of your 

 members, have taken no inconspicuous part. It adds impressively to 

 the honor you have this day conferred on me that your action is the 

 deliberate determination of competent, severe, impartial judges. I can- 

 not adequately express my feelings of gratitude in such a presence, pub- 

 licly pronouncing its approval on what I have done. 

 " I am, gentlemen, very truly yours, 



" JOHN W. DRAPER." 



The investigations and memoirs referred to by the committee of tin- 

 Academy are contained in this volume. 



