Displayin two datsets one below the other in a gridview

Question

Hi ,
Could anyone tell me how to display two datasets one below the other in a gridview. The columns of the two datasets are the same but the values are retrieved using different stored procedures. How do i put the datasource and bind it.
Gridv1.DataSource = ds1;
Gridv1.DataSource = ds2;
Gridv1.DataBind();
It doesnt work. Please help me