"A vestibule /ˈvɛstɪbjuːl/ is an anteroom (antechamber) or small foyer leading into a larger space, such as a lobby, entrance hall, passage, etc., for the purpose of waiting, withholding the larger space view, reducing heat loss, providing space for outwear, etc. The term applies to structures in both modern and historical architecture since ancient times. In modern architecture, vestibule typically refers to a small room next to the outer door and connecting it with the interior of the building."
That's wonderful, Mr. Mitcham, but we really don't know if Harry Holmes, himself, knew the correct meaning of the word now do we.
Regardless:
CONFLICTING TESTIMONY BY POSTAL INSPECTOR HARRY HOLMES:
Mr. BELIN. By the way, where did this policeman (B) stop him (O) when he (O) was coming down the stairs at the Book Depository on the day of the shooting?
Mr. HOLMES. He said it was in the vestibule.
Mr. BELIN. He said he was in the vestibule?
Mr. HOLMES. Or approaching the door to the vestibule. He was just coming, apparently, and I have never been in there (in the 2nd-floor lunchroom, right???) myself. Apparently there is two sets of doors, and he had come out to this front part.
Mr. BELIN. Did he state it was on what floor?
Mr. HOLMES. First floor. The front entrance to the first floor.
....................................................................
In my humble opinion, there is nothing near the front door on the TSBD's first floor that comes close to being what Belin and Holmes are describing in the first part of Holmes' testimony, above.
E.g., "coming down the stairs," "approaching the door to the vestibule," "I have never been there myself," "two sets of doors," "front part".
That's all 2nd-floor lunchroom stuff as far as I'm concerned.
So, why the heck did Holmes say, "First floor. The front entrance to the first floor."
-- Tommy