When Capt. Crane receives a phone call on the bridge, he is handed a
compact grey telephone. The phone he is handed is an early Western
Electric "Trimline" phone, which, although in hindsight is exactly
appropriate for the year the episode is set in (1978), was brand-new in
1966, quite scarce and not yet widely available. The phone he is handed
is a "wall model", intended to be mounted vertically, not used on a flat
surface. After his call, Hedison keeps his hand on top of the phone on
the desk, presumably to keep the receiver from sliding off onto the desk.