Early German Rose engines.

Early German Rose engines.

I have nothing in writing about these early German machines.
When you can fill in the blanks on history and where we can see these beauties please do let us know.

These two are from round about 1750 and when i look at the quality and superb forms i can say this is craftsmanship at its best.
And how much time did they ( the craftsman ) spent to produce a machine like this?