Hi Gang......Guess what? I'm stuck.
I don't want to resort to a walkthrough, but the balloon man is driving me nuts with his repeated (and I DO mean repeated) requests for a helium cylinder (needed for repairs) that is supposed to be at the University (which is really the "Academy.") I've found three doors leading off the circular foyer in the University. One goes outside, one goes to the library and the other to the Lab. I've found no helium tank. Got a hint, please?