How do you extract a bitmap from a TGraphicField?

I am going nuts.

Here's what I am doing

1. Drop a TClientDataset, a TImage, and a TButton on a form.
2. Set the Clientdataset1.Filename to biolife.xml

3. Double click on the button and add the following code:

   procedure TForm31.Button1Click(Sender: TObject);
   var
     BF: TBlobField;
     BS: TStream;
     BM: TBitmap;
   begin
     ClientDataset1.Open;
     ClientDataset1.First;
     BF :=  ClientDataSet1.FieldByName('Graphic') as TBlobField;
     BS := ClientDataSet1.CreateBlobStream(BF, bmRead);
     BS.Position := 0;
     BM := TBitmap.Create;
     try
       BM.LoadFromStream(BS);
     finally
       BM.Free;
     end;
   end;
   

Run it. When I do, I get "Bitmap image is not valid".

Huh? That data has been a bitmap for years -- what is wrong?