How can i use two or more table in a single dataset

foreach(DataTable dt in ds.Tables)
{
    Console.WriteLine(dt.Rows[0][1].ToString());
}

create procedure spDataset
as
begin
select * from tblCountry
select * from tblCity
end

protected void Page_Load(object sender, EventArgs e)
    {
        connection();
        cmd.CommandType=CommandType.StoredProcedure;
        cmd = new SqlCommand("spDataset", conn);
        da = new SqlDataAdapter(cmd);
        da.Fill(ds);
        GridView1.DataSource = ds.Tables[0];// For first select query(table) in Stored procedure, that is select * from tblCountry
        GridView1.DataBind();
        GridView2.DataSource = ds.Tables[1];// For first select query(table) in Stored procedure, that is select * from tblCity
        GridView2.DataBind();
    }

create procedure spDataset
as
begin
select * from tblCountry
select * from tblCity
end