"Seo RN bat oat e a aes oS es tt ie ei ner, eee ran Sa Cie bese laces anh ai ead 
American Association. 305 
perhaps, as has been already suggested by many physicists, upon 
the vibrations or motion of light or upon some other physical 
action which pervades the universe.” The address passes next to 
the moon and considers the unsatisfactory condition of the lunar 
theory ; to the planets and discusses the accordance of theor 
with observation in their motions, expressing the opinion that 
“ the tremendous array of negative evidence from the most trust- 
worthy observers, with the best equipment and opportunity, 
makes it little short of certain that there is no Vulcan in the plan- 
etary system ;” to the sun itself, giving a masterly statement of 
the difficulties yet unconquered in the theory of his constitution ; 
experience ;” and finally to the problems of stellar astronomy ; 
closing with a few well chosen words upon the advantages of the 
Study of truth for its own sake, since “in the investigation and 
discovery of the secrets and mysteries of the heavens the h 
um 
intellect finds most invigorating exercise and most nourishing and 
9 
growth-making aliment 
f the papers read, it will, of course, be impossible to speak in 
detail. Those communicated to Section A numbered 37, those to 
Section B 42, and those to Section C 29. Among the physical 
papers, those of Professor Mendenhall “ On the variation of the 
resistance of carbon under pressure ;” of Professor W. A. Rogers 
“Additional observations confirming the relation: Metre des 
r 
H. Pickering “ Photography of the infra-red region of the spec- 
of rs Daniell cell and the strength of the zinc sulphate solution ; 
r 
tion of chemistry, those of Dr. Springer on “ Torsion balances ;” 
of Professor Wiley “Optical methods of estimating sugar in 
. ‘ 
> 
Miss Abbott “ Preliminary analysis of the bark of Fouguieria 
Splendens Engl.” may be specified. ee 
The number of members of the British Association resent at 
Philadelphia was gratifyingly large. A special train from Mon- 
treal to Philadelphia on Thursday brought about 200; and more 
