How can I get down to the chasm

Hint 1 of 8:

You'll probably need some rope to climb down.

Hint 2 of 8:

Use the rope from the fort.

Hint 3 of 8:

Now you'll have to tie some more rope to something else.

Hint 4 of 8:

Have you been to the dry river bed?

Hint 5 of 8:

There's some rope hanging on the "sick" guy.

Hint 6 of 8:

Figure out how to fill the river bed...

Hint 7 of 8:

and get the rope off of the guy at the river bed.