( ciii ) 



I shall read to you the following ohservations made to me in 

 a letter by Professor Stokes of Cambridge: "Mr. Burton's paper 

 contains the result of a series of careful observations on the zodiacal 

 light, made under circumstances much more favourable than present 

 themselves in our latitudes. He applied himself more especially 

 to an examination of the spectrum of the light, for which he 

 employed a spectroscope specially constructed for the examination and 

 measurement of the spectra of extremely faint objects, which was 

 obtained by means of a grant entrusted to him by the Academy. The 

 bright line discovered by Angstrom in the spectrum of the zodiacal 

 light, and supposed by him to agree in position with the chief line 

 of the spectrum of the aurora, was observed and measured on several 

 occasions, and the resulting wave-length differs too much from that 

 determined by Angstrom for the auroral line, to allow us to suppose 

 the two to be identical. As the difference, however, is not great, and 

 an observer so accurate as Angstrom (who, however, appears to have 

 only seen the zodiacal line when it was too faint for measurement) 

 supposed the two lines to be the same, it would seem desirable that 

 Mr. Burton should measure (if he has not clone so already) the 

 chief auroral line with tJie same instrument that he employed for the 

 zodiacal light. 



" Mr. Burton has also noticed and measured the position of a dark 

 band in the zodiacal light which does not seem to have been 

 previously observed. 



''The zodiacal light showed also distinct traces of polarization, 

 proving that it is in part reflected light, wliile the character of the 

 spectrum proves that the object is also self-luminous, and the 

 establishment of the non-coincidence between the auroral and zodiacal 

 lines prevents the danger we might have incurred of looking to the 

 aurora for an explanation of the physical condition of the body which 

 is the origin of the zodiacal light." 



I have now to add a few words in connexion with the Archaeolo- 

 gical department of this body, and am anxious to bring forward one 

 or two points in reference to the futui'e action of the Committee of 

 Polite Literature and Antiquities. 



The first being Sir John Lubbock's Ancient Monuments Bill, I 

 sincerely hope that we may see this important measure passed during 

 the coming Session of Parliament, and no effort should be spared by. 



