528 
ON RECENT CHANGES IN 
Oxygen 8. 
Oxygen = 
Nitrous Acid .... 
hno 4 . 
. hno 2 
Nitric Acid. 
HIS O e . 
. hno 3 
Essential Oil of Almonds 
0 !4 H 6 0 2 . 
. c 7 h 6 o* 
Benzoic Acid .... 
c 14 h 6 o 4 . 
. c 7 h 6 o 2 
Blue Indigo .... 
0 i 6 TT 5 N0 2 
. C,H,NO 
Isatin. 
c 16 h 5 no 4 
. C 8 H 5 NO, 
Aldehyde . 
c 4 h 4 o 2 . 
. c 2 h 4 o 
Acetic Acid .... 
c 4 h 4 o 4 . 
. (J 9 ii 4 U, 
etc. 
etc. 
etc. 
Again, when oxygen is removed by processes of reduction from compounds 
containing it, the removal invariably occurs in quantities representing 16 or 
a multiple of 16 parts by weight. 
Thus:— 
HN0 6 + 8 H = NH 3 + 3H 2 0 2 
or HN0 3 + 8 H = NH 3 + 3H 2 0 
Benzoic Acid. Benzoic Aldehyde. 
^14^6^4 + ^H = C 14 H 6 0 2 + H 2 0 2 
or *C 7 H 6 0 2 + 2H = C 7 H s O -f H 2 0 
Tartaric Acid. Succinic Acid. 
^ 3 ^ 6^12 + — CgHgOg + 2H 2 0 2 
or C 4 H 6 0 6 + 4H = C 4 H 6 0 4 + 2H 2 0 
When water is liberated from a compound, it is never in proportion repre¬ 
sented by H O, but by 2 H O (O = 8 ). 
Nitrate of Ammonia. Laughing Gas. 
NH 4 N0 6 = JS t 2 0 2 + 2 H 2 0 2 
or NH 4 N0 3 = N 2 0 + 2H 2 0" 
Acetate of Ammonia. Acetonitrile. 
NH 4 C 4 H 3 0 4 =:C 4 H 3 N + 2H 2 0 
or NH 4 C 2 H 3 0 2 = C 2 H 3 N + 2H 2 0 
Lactic Acid. Anhydrous Lactic Acid. 
^ 6^6 ^6 — C 6 H 4 0 4 H 2 0 2 
or C 3 H 6 0 3 = C 3 H 4 0 2 + H 2 0 
Or in processes of oxidation 
Alcohol. Aldehyde. 
C 4 H 6 0 2 + 20 = C 4 H 4 0 2 + H 2 0 2 
or C 2 H 6 0 + O =C 2 H 4 0 +H 2 0 
The above examples illustrate the manner in which arguments have been 
drawn from considerations purely chemical, and exhibit some of those which 
have been influential in inducing the modifications in the atomic weights of 
oxygen, and the other non-metallic elements ; but innovation has not rested 
here; the metals have themselves been the subject of much discussion. 
Diatomic radicles in organic chemistry have long been recognized, but it was 
more particularly the strong analogies urged by Wurtz as existing between 
the compounds of ethylene and those of many of the metals that brought 
about the alteration in the atomic weights of the latter. It is, I believe, ad¬ 
mitted on all hands that the reactions of ethylene, the mode of its transfor- 
* C = 12. 
