OneGuyFromBarlick

No. Big clue, think personal hygiene.

Is it for removing ear wax?

I was going to say a snuff bottle but you've thrown me with the personal hygiene clue...

Think of a personal hygiene situation we don't encounter routinely today.

Nits, BO, ???

Is it a pot for holding some sort of nice smelling substance to mask the stench of the unwashed?

Like Kev says - a vinaigrette - as in Antiques Road Show, and not the salad dressing sort?

Gloria is the closest but not quite right. (I didn't know these things existed.)
No, sorry, not for masking bad smells.

Does it contain dusting powder for the treatment of body lice?

No, but you are on the right subject. Not lice but fleas, but what exactly is the object?

18th century flea trap worn under clothing?

omg ! Don’t even want to imagine it.

Yes Gloria! It's a flea trap. I didn't know they existed until I found this one.
From what I can make out they were baited with the skins of dead fleas, evidently this attracted the others and then they could be killed. I'm glad we don't need them now.

Yessss, that was a good one Stanley, don’t they sound disgusting?

That was a difficult one Stanley, well done. It's probably also a good example of an early use of natural pheromones to trap insects. Artificial pheromones are used now.

Here's a mystery object...
The main question is what's the function of this building. The secondary question is where is it located?

Is it for drying timber?

Sorry Stanley, but it isn't meant for drying timber.

Drying hops?

Keeping people dry?

Not for drying hops, Gloria.
It would stop people from getting wet on a rainy day but there's more to it than just that. But you're right that it was for people, not hops or timber.
Think how much it must have cost to get it built.

Is it for some sort of recovery process, patients at a hospital or clinic or for the wealthy so they could have a walk without getting wet in the rain?

The architecture looks somewhat church like...

A detached cloister for nuns.

It's on a slight elevation. Could it have been shelter for spectators of some game or event?

Is it for use as the long gallery in large manor houses, for exercise when the weather was poor, this way they would get fresh air as well?