Hoping to cover both Val and Celeste Keth steps up drawing out his dagger and attacks both of the jellies.

Against the original with a tomahawk: Attack: 21 Damage: 5

Against the copy with a dagger: Attack: 16 Damage: 1

Ruling: Keth will hack with his tomahawk and slash with his dagger.

Keth hacks with his tomahawk doing 5 points of damage to new Jelly 1.
He also slashes with his dagger at Jelly 2. The dagger sliced through the jelly and it separates.....into 2 smaller Ocre Jelly's (new Jelly 2 and Jelly 3)

Round 4 actions:
Celeste: 16
Val: 15
Clay: 14
Rictor: 11
Ochre Jelly 1: 6 (This Jelly seems to be reduced in size even more as some of its body drips off it)
Ochre Jelly 2: 6
Ochre Jelly 3: 6
Keth: 4

(Not sure if we started a new round of combat or not, but this is for when Rictor's turn comes up)

Rictor throws his hands up in frustration as yet more of the smaller and smaller jellies appear with each hack and slash of his friends' weapons. Noticing that one was nearly dripping into nonexistence he instead aims at the ooze that just appeared.

Eldritch Blast at Ochre Jelly 3: Attack: 12 Damage: 10

Begrudgingly allowing the storm in her saber to die, Celeste disengages, "We need to think of running!"

(Action, disengage, then get 30 feet away from the jelly.  She'll start drawing her crossbow)

Val fires the rifle again

Attack: 4 Damage: 11 

Celeste retreats from the melee combat and changes weapons. 

Jelly 1 takes an attack of opportunity:
Hit: 15 and misses.

Val retreats, changing form as he goes. He draws his Rifle, aims and fires. The shot goes wide and bounces off the wall a couple times.

However, the sound in such an enclosed place is the problem. 
Everyone takes : 3 (make a Con save. Success means you take 1/2 damage. Failure means you take full damage and are stunned for 1 round.)

Keth Con save: 12

If not stunned: He targets two seperate jellies, Specially if they look they may be trying to persue any of the other party members.

Tomahawk Attack: 16 Damage: 5

Long Knife: Attack: 13 Damage: 2

Con: 11

"Damn it that rifle is loud!"

*Clay will try to distract the jellies while everyone retreats if that is the group consensus.  Clay continues to use the torch.*

Rictor can hardly string together a proper sentence as he lets loose a litany of swear words, holding his ears. 

Con save: 18

Assuming he isn't still in deafened agony he casts another Eldritch Blast at the remaining jelly.

Attack: 25 Damage: 8

Val con save 5 

(moving forward a bit)

Celeste's Con Save: 23

(OCC: I apologize I did not mention the DC to the save. it is 12-still working the kinks out of my DMing)
Celeste makes her save. 
Both Val and Clay take 6 points of damage and the sound was so great they both cover their ears and cry out in pain a bit. Both lose an action)
Everyone else takes 3 points of damage.
Rictor fires his "Pistol' once more, striking Jelly 1. It shivers and there is a faint, audible sound as it shrinks a bit and dissolves.
Keth attacks Jelly 3, the only remaining jelly. He hacks and slashes the creature. Parts of its body slosh off with each attack. Again there is a faint, audible sound as the creature withers and becomes a pool of sticky, smelly ooze. 

With that, the Orche Jelly has been defeated.

Party actions?

Rictor twirls his empty pistol and blows imaginary smoke from the barrel, holstering it with a flourish.

"You guys got fried!" He looks at those of the group that had gotten up close and personal with the horrible, acidic jellybeasts.

"I say we rest up and lick our wounds for a spell."

“Yup,” Val says hunched over and hurting. “Celeste found a book.” He points at where it was.

"I... I agree.  That was unsettling.  A rest would be nice.  As far as the book, here ya go."  She then tells them what she saw while flipping through it.  "Seems like a bunch gobbledy gook to me."

Rictor takes the book and finds a spot to hunker down and thoroughly look through the pages while he recuperates.

Arcana check (to see if the book is magical or has any spells or rituals in it): 22

The party gathers together after the battle to rest and mend some wounds. 
Celeste presents the book and Rictor grabs it and goes sits down, looking through the pages.

Celeste also remembers she found a couple of other items as well: A camp knife, a pair of old smelly boots and, a single sock.

Rictor starts thumbing through the book and lets out a horrible scream. You all look to him as he throws the book from him and his hand is smoldering a bit. (cover this in a private message.)

“What’s wrong??” Val jumps back up

Rictor lets out a wail of pain and instinctively tosses the book, trying to put as much distance between himself and the pages as possible.

He shakes his head, cradling his burnt hand and rocking, curled up in the fetal position for a moment. "It... it burned me. The holy symbol."

(Continuing)

The party glances over at the book and for an instant you all see a faint glow of light coming from inside one of the pages.

Val touches it