Mr. Nixon’s Table of observed Terrestrial Refractions. 479 
proposition which I at first laid down, namely, that the che- 
mical power of a current of electricity is in direct proportion 
to the absolute quantity of electricity which passes. (377. 783.) 
They prove too that this is not merely true with one substance, 
as water, but generally with all electrolytic bodies ; and further 
that the results obtained with any one substance do not merely 
agree amongst themselves, but also with those obtained from 
other substances, the whole combining together into one series 
of definite electro-chemical actions.(505.) I do not mean to say 
that no exceptions will appear ; perhaps some may arise, espe- 
cially amongst substances existing only by weak affinity: but 
I do not expect that any will seriously disturb the result an- 
nounced. If, in the well-considered, well-examined, and I may 
surely say, well-ascertained doctrines of the definite nature of 
ordinary chemical affinity, such exceptions occur, as they do in 
abundance, yet without being allowed to disturb our minds 
as to the general conclusion, they ought also to be allowed, if 
they should present themselves at this the opening of a new 
view of electro-chemical action: not being held up as obstruc- 
tions to those who may be engaged in rendering that view 
more and more perfect, but laid aside for a while, in hopes 
that their perfect and consistent explanation will finally ap- 
pear.” 
With regard to my having overlooked the cause of the 
diminution and cessation of voltaic action on the oxide of 
antimony, I do not know how that can well be said, for Ber- 
zelius’s statement seems in parts to be almost a copy of the 
reasons I have given: see paragraph 801. of the Seventh Series 
of my Researches. My explanation is actually referred to in 
the account of the action on the oxide of antimony at para- 
graph 693., but by a misprint 802. has been stated instead 
of 801.* I am, Gentlemen, yours &c., 
M. Farapay. 
LXXXII. Table of observed Terrestrial Refractions. By 
Joun Nixon, Esq.t 
THE following table of mean refractions is founded on 
measurements obtained at 61 stations on 162 arcs, of 
various lengths from 1! 9" to 21! 48", amounting together to 
17° 59’. The observations were made on 515 different days 
of the years 1821 to 1824, 1827 to 1833, and 1835. The 
average altitude above the level of the sea of the 162 arcs is 
1730 feet. 
* This reference is correctly made in Lond. and Edinb. Phil. Mag,, vol. y. 
p. 170.—Epir. 
+ Communicated by the Author. 
