I have explored the dawnguard base very much in the last two weeks, but for some reason never glanced up in the main room. Tonight I did of curiosity and noticed something strange.
The hole in the roof has some sort of small contraption hanging from the side. It is two rods with a small gyro-looking object attached to the end.
I climbed to the second floor to get a closer look but still cannot tell its function. I fired arrows, spells, shouts... Even auriels bow at it and nothing happened.
Now, I love secrets and am always looking for them... I may be missing something completely obvious, or the thing may be a decoration, I cannot tell.
I make this thread to ask that next time you go in the base you give it a look and tell me what you think it is, if someone knows it can put my curiosity at ease.