14 
Transactions Texas Academy of Science. 
When the migration is intramolecular a stereoisomerie compound is 
the product of the change; when the migration is extra or inter- 
molecular disruption of the molecule takes place. Loew 11 points 
out the necessity of distinguishing between “potentially labile and 
kinetically labile compounds ; in other words, between static labile 
and dynamic labile” — using the potential chemical energy in the 
sense of intramolecular chemical energy. Nitroglycerole and cer- 
tain other explosive organic compounds represent the potential type, 
while examples of the kinetic are found in the aldehydes and 
ketones. 
The energy stored in a labile compound is beautifully illustrated 
in the explosion of the trinitrate of glyceryl — CH 2 (0N0 2 ) . 
CH(0N0 2 ).CH 2 (0N0 2 ), which, when heated to 257° C., or when 
struck, explodes with great violence. The products of the decom- 
position are represented by the equation : 
4C 3 H 5 .(N0 3 ) 3 = 12CO 2 + 10H 2 O + 6N 2 +O 2 . 
At the temperature of the explosion all these products are gases, 
and at atmospheric pressure will now occupy the space of about 
10,400 litres, having expanded about 18,324 times its original 
volume. 
Another instance is that of mercury fulminate [(C:N.O) 2 
Hg 2 +V 2 H 2 0], which develops a pressure of 43,000 atmospheres by 
detonating in its own volume. 
Chemical changes partially or completely destroy the statically 
labile compounds, while the dynamically labile compounds readily 
pass into isomeric or polymeric compounds as a result of atomic 
migrations, or by polymerization. The classic illustration usually 
given of the production of an isomeric compound produced by 
atomic migration is Woehler’s famous discovery: the transforma- 
tion of ammonium cyanate into urea, which he accomplished in 
1828, by evaporating an aqueous solution of ammonium isocyanate. 
The transformation is represented by the equation: 
nh 2 
0:C:N.NH 4 — f 0:C/ 
\nh 3 
Many others can be cited. 
Noting that labile compounds are more easily attacked by chemi- 
cal agents than stable ones, Loew 12 has elucidated the action of 
many, poisons. He says : “A systematic toxicological review shows 
us, among other things, that all compounds acting upon aldehydes 
and all that easily attack labile amido-groups are poisonous for all 
kinds of living protoplasm, which fact led me to infer that the 
