I was in the presence of one of Prince Philip's witticisms once back in the 1970s!
I was in a small crowd that had gathered in a private location that was hosting lunch for some event that the Queen and Prince Philip were attending. The royal party and retinue of 20 or 30 people approached down a long gravel path with around 50-100 observers lined behind a rope barrier about 10 or 20 yards separated. The gentleman standing next to me with his family was taking pictures with an SLR camera with a telephoto lens. Suddenly the prince veered off from the procession and bounded over to the photographer. "Good morning," said the Duke to the man, "you must be an American. Are you?"
"Why yes," said the man, completely nonplussed by this piece of royal clairvoyance "How ever did you know that, your royal highness?" he asked evidently quite overawed by the Prince's erudition.
"Oh, it was easy," said Philip, "I could tell by the size of your camera!" and after a short stunned silence all in the vicinity laughed politely in response to this leaden joke.
There followed actually a short conversation between the two men about f. stops and focal lengths which indicated that the royal had a fair knowledge of photography. This interruption to the progress to lunch had stopped the royal party including the Queen and after a minute or two she also broke off from the procession and took a few steps towards us and in a distinctly irritated 'stage whisper' voice hissed at her husband "Philip! Do come on. You are keeping everyone waiting!" The Prince instantly complied apologising briefly to his interlocutor for the curtailment of their discussion as he turned and disappeared with her majesty through an archway!
John