Help assess the pattern. Arnold Who is he?

[Katerina Arnold]

Dear connoisseurs of art, help!
There are 2 pictures: 30 to 40 cm, oil on canvas.
In the deplorable condition of work (there are gaps, a layer of soot, some), but nevertheless it is clear that a Europe no later than the 19th century and author Arnold.
according to the owner of the picture taken out of Europe during WWII.
Who is it Arnold? Is it worth it to restore and sell it? How much could it cost?
Advance grateful for the advice.