Experimenting on a raft anchored on the river Elbe, Alfred Nobel tries to make nitroglycerine safer to handle. Finds that the addition of kieselguhr turns nitroglycerine into a dough that can be kneaded, and calls it "dynamite".
Rafts certainly are not something that exist.
( z1 something :polarity - :ARG1-of ( z2 exist ) :domain ( z3 raft ) :mod ( z4 certain ) )