hard pus in eye!!!

Now I am no expert when it comes to the anatomy of the chicken eye but I assume it will  be very similar to that of ours which I am of greater knowledge, this sounds like a blocked nasolacrimal duct, in adults it would normaly require surgery to unblock. It would be best for the vets to have a look as it could cause infection if not sorted.

Edit: I could be a million miles away here, but having googled 'blocked nasolacrimal duct in poultry' it seems to of thrown up eyeworm as a possiblility, this causes irritation and conjunctivitis type symptons. Lets hope the vets can sort it for you.