"That also explains the extra windows on the cupola."
To you maybe, explain to us layman.
Well certainly. The cupola is the raised center section, there are two chairs up there so the rear end crew had a better view of the train ahead of them. But usually they just look like this, rather than the above version with extra slanted windows:
As well as a place to sit, the crew had a radio to communicate with the head end locomotive, a pressure gauge to monitor air brakes and a pull cord to initiate an emergency brake application if so required.
Other caboose info:
The main floor also had a seat at each end by the end window along with a desk for taking care of paperwork, another emergency pull cord and radio, switches for the lights, both inside and out (red, green and track lights). There was an oil heater at each end, a large water tank (regularly sterilized), sink, stove, a chemical toilet, bunks for sleeping and supply lockers.
The supplies included spare air hoses in case something blew apart during the trip, spare knuckles for the couplers, brake shoes and brake shoe keys, hammers and bars and basic tools. Each door had a holder with a selection of both yellow and red flares and track torpedoes. There were personal lockers for the crews as well, some cabooses were dedicated to certain runs and had the same crews using them all the time, others went across long distances and would be attached to any needed train for the return trip.
Short distance runs used a caboose with a diesel generator for power, keeping the lights going. The radios had their own batteries and were the size of a small lunch box, portable to be used out on the track if needed. Long distance cabs (most of them) had a bank of batteries in a tray, and a generator that was driven by a driveshaft coming off one of the main wheels like this example:
For a couple of years I was the lead hand in the caboose maintenance section, taking care of these cabs before each trip.