Thomas,
Congratulations on your new acquisition! I hope you did not find it at some of the flea markets I frequent in your neighbourhood.....
The 35mm Elmar was Leitz's first wide-angle lens, introduced in 1932. It was a good lens for its time, but I think that you will find that it is not a particularly stellar performer. The 50mm Elmar was a far better lens, but since the 35mm Elmar was the only 'wide game' in town in the 1930's, nobody complained.
Check the lens for haze - shine a strong light through the elements; from your photo I do indeed detect some. This would reduce the performance even further.
All the best,
Jan