382 Addresses delivered at the Commemoration 



during any lines. The total absence of lines cannot, however, be 

 interred from our observations, as the apparatus was not very care- 

 fully adjusted. 



Euchlorine produced a number of broad lines at irregular inter- 

 vals in that part only of the spectrum which was extinguished by 

 chlorine. 



Lastly, the vapour of indigo was tried, but without producing 

 any lines. The near approach of the temperature at which indigo 

 is decomposed to that at which it is volatilized, made it difficult to 

 obtain enough of the vapour to give a decisive result in this case. 



W.H.Miller. 



COMMEMORATION OF THE CENTENARY OF THE BIRTH OF 

 DR. PRIESTLEY. 



Addresses delivered at the Commemoration of the Centenary of the 



Birth of the Rev. Joseph Priestley, LL.D. F.R.S., regarded as the 



Founder of Pneumatic Chemistry, holden in Freemasons' Hall, 



London, March 25, 1833. 



[In our last Number we briefly noticed the Commemoration of the 

 Centenary of the Birth of Dr. Priestley, giving the names of some of 

 the patrons and cultivators of science who were present. We now 

 redeem our promise of publishing a more complete view of the pro- 

 ceedings, by giving a report of the addresses which were delivered on 

 this interesting occasion.] 



At the commencement of the proceedings especially appropriate 

 to the commemoration, William Babington, M.D. F.R.S., Presi- 

 dent, addressed the assembly to the following effect : — 



Gentlemen, — I am very desirous to have it distinctly understood, 

 that I have not presumed to be your Chairman, on the present me- 

 morable occasion, in conformity either with my own inclination, or 

 my own judgement, but in compliance with the request of several 

 much respected friends of our Committee of Stewards, with whose 

 wishes I found it impossible not to comply. I therefore trust that 

 you will have the kindness to make the necessary allowance ; and I 

 am not without hope that my best endeavours, aided by your friendly 

 assistance, will effect the object of our present meeting to our entire 

 satisfaction. 



Gentlemen, you must already be sufficiently aware that the object 

 for which we are now assembled is to commemorate the Centenary of 

 the Birth of a very distinguished and highly gifted individual, Dr. Jo- 

 seph Priestley, the principal founder of pneumatic chemistry. I 

 had the gratification of knowing him personally, but not until he had 

 himself, by the novelty and importance of his researches, become 

 known to all the world. The principal founder of pneumatic chemis- 

 try he undoubtedly was, if not the sole inventor ; for although it may 

 be granted that he had, in a few isolated instances, been anticipated, 

 yet I may venture to assert, without fear of contradiction, that, du- 

 ring the period in which he was actively engaged in that department 

 of experimental science, he gave more evidence of original genius, 

 exhibited more novelty, made more numerous experiments, and oh- 



