[Gmsh] Different element sizes in different spatial directions?

[Martin Meyer]

Hi,

I'm pretty new to gmsh, and so far I haven't succeeded in creating a  
mesh with different element sizes in different spatial directions (for  
instance a 100m*100m square with average element sizes of 10m in x  
direction and 1m in y direction).
Is this possible, and if so, can you show me how to do that (either  
script or GUI)?

Thanks in advance for your thoughts,
Martin