212 Proceedings of the Royal Society of Edinburgh. [Sess. 
be taken = 12, but he retains, as I have already more than once stated, 
0 = 8. I now give, in three columns : — 1st, the formulae from the Annates 
de chimie et de physique paper; 2nd, those from the Philosophical Magazine 
paper; 3rd, the formulae obtained from these by putting 0 = 16. While in 
the Gomptes rendus paper Couper contented himself with quite simple 
examples, in the fuller papers he gives formulae for substances with a more 
complicated composition. 
Propyle Alcohol. 
1 
0— OH 
C- 
C 
•()••• OR 
C" 
OH 
1 
H 2 
H 2 
H 2 
C- 
-H 2 
C 
H 2 
c 
H 2 
C- 
-H 3 
c 
H 3 
C" 
H 3 
Butyle Alcohol. 
( 
K 
o 
1 
o 
C 1 
O' 
0 OR 
C" 
OR 
1 
H 2 
H 2 
H 2 
C- 
-R 2 
0- 
H 2 
c- 
PI 2 
C- 
-H 2 
c 
H 2 
c 
H 2 
C- 
-H 3 
c- 
H 3 
C" 
H 3 
Butylic-ethylic Ether. 
( 
0 — 0 ) 
°! 
} C 
C' 
" 0 c 
C " 
( 
1 
R2 H 2 ) 
H 2 R 2 r 
H 2 
c- 
1 
-H 2 H 3 — C 
0- 
II 2 II 3 c 
H 2 
1 
c- 
~H 2 
c 
R2 
C" 
H 2 
c- 
-H s 
c- 
-R 8 
0" 
H 3 
Formic Acid. 
r 0- OH 
O 
c 
p: 
0 
CP 
O 2 
c 
O 2 
c. : 
0 
H 
H 
'••H 
Acetic Acid. 
1 0— OR 
c < 
\ 
c 
0 ' OH 
O' 
"OH 
\ O 2 
O 2 
"0 
C- 
-H 3 
c 
"H 3 
c 
H 3 
H 2 
'C 
