In The Lord of the Flies, when the first attempt to flush Ralph fails, what is the next attempt?

By the end of the novel, Jack Merridew is on the war path
with only one objective in mind: Ralph.  He and his hunters sweep the jungle looking for
their former chief.  When Jack discovers the dense thicket where Ralph might be hiding,
he orders the hunters to release a boulder from the top of the hill at Castle Rock to
come crashing through the woods with the hope of flushing Ralph
out. 

When Jack's first attempt fails, he devises another
devious plan intended to make Ralph run--the hunters light the thicket on fire.  Ralph
hears it first, unsure to make of the "curious trickling and then a lower crepitation as
if someone were unwrapping great sheets of cellophane" (194).  Ironically, Jack's fire
tactic does succeed in rousting Ralph from his hiding place, but it is also this same
blaze that is spotted by the naval ship which results in Ralph's salvation and rescue.