Spot on with the cars Mike, the flag on the port yardarm, looking through a magnifying glass at the origional, is indeed the blue peter so you're right on target, preparing to sail. I was luck to catch her for the photo! Further aft she's flying some thing I can't make out over the answering pennant, any ideas what that meant?
Now Norman, I'm learning something from all this even if it's about Classic cars! I remember the appalling vacuum operated wipers which Ford loved around then, the faster you went the slower they wiped until you reached a speed when they stopped altogether, interesting concept! Me, I prefered Kent clearview screens!! I've also learned it was the practice to hoist the US ensign at the foremast truck on the day of departure, always wondered why she was flying that. My thanks to Mike for that one.
I agree with Principe Perfeito that the two flags on the mainmast are the house flags of Cunard White Star, as the company then was. It was the practice of a lot of ships in the "good old days" to fly the ensign of the country of the next overseas port of call on sailing day - it depended, I suppose, on how "traditional" the people on board were? I remember we did it on a couple of Port Line ships when I was with that company - might have been that the Masters were "older school" men at the time.
Mike, many thanks for that, it's not a practice I ever came accross in tankers. None the less we did observe the traditional flag etiquettes of "House Jack" on forward jack staff at first rope ashore, red ensign down from the signal mast and up on the poop etc. On some ships we used the "Blue Peter" prior to departure but the practice wasn't universal. As you rightly say, some things depended on the Master and views.