What has Euler got on his head here?

[dipole]

This is a very well-known portrait of Leonhard Euler, which I'm sure most people have seen before, but does anyone know what the heck he's wearing on his head?

http://upload.wikimedia.org/wikipedia/commons/d/d7/Leonhard_Euler.jpg

It looks like someone threw a dirty old rag on him - does anyone know what the name of that headwear is, and what kind of function it serves?

 

[dlgoff]

Is it a Do-rag?

 

[Enigman]

http://books.google.com/books?id=75...gQ6AEwAg#v=onepage&q=euler cloth head&f=false
silk cloth to hide a bald head and no wig because of some custom.

 

[dipole]

http://books.google.com/books?id=75...gQ6AEwAg#v=onepage&q=euler cloth head&f=false
silk cloth to hide a bald head and no wig because of some custom.

Ha nice find, thanks for posting!