Dreams! adorations! illuminations! religions! the whole boatload of sensitive bulls***!
The speaker considers "dreams," "adorations," "illuminations," and "religions" all good things, perhaps the only good things.
They belong to the "sensitive" part of the soul. But they have been treated like "bulls***" and bartered away by the "boatload" for next to nothing. To the capitalists who only care about prices and profit margins, they are just a bunch of honky.
Breakthroughs! over the river! flips and crucifixions! gone down the flood! Highs! Epiphanies! Despairs! Ten years' animal screams and suicides! Minds! New loves! Mad generation! down on the rocks of Time!
The speaker adds a new twist to the image of the river, which now seems to be headed for a waterfall dividing the present from the past.
Imagine things like "epiphanies" and "new loves" being sucked over the edge of Niagara Falls and landing on the sharp "rocks of Time." They have no place in the modern age and lie stranded on these "rocks."
Real holy laughter in the river! They saw it all! the wild eyes! the holy yells! They bade farewell! They jumped off the roof! to solitude! waving! carrying flowers! Down to the river! into the street!
More good things, including "holy laughter" and "holy yells," get tossed into the river. The "best minds" from the first line of the poem noticed that the goodies were disappearing, and they didn't want to stick around to see the end of the story.
The speaker makes another vague reference to suicide. It appears the "best minds" from the first line "jumped off the roof" of their apartment and fell "into the street" below.
The images of the downward flowing river or waterfall and the jumping people fuse together in this line. Not a happy note for the end of the second section.