I have just discovered Judge Dee. Yesterday I read The Chinese Bell Murders, the only one of these books that my local library has. What a wonderful book! I can see from the list at amazon that there are a lot more of them. But more on Judge Dee elsewhere, later.

What made me curious was the constant references to the characters putting stuff up their sleeves - parcels, knives, strings of cash, papers, the odd bar of gold or silver. If I put something up my sleeves, it would fall out when I put my arms by my sides. Since the Chinese during the Tang era wore robes with large openings at the wrists, I had to wonder how anything would stay up there. I was thinking there might be inner sewn pockets, but I can't find any reference to such.

I've found an image showing a Shenyi. Maybe when the arms are lowered those large pouchlike sleeves somehow close themselves off?

Do you suppose this is the origin of the saying "he's got something up his sleeve"?