files deleted from EXTERNAL HD do not appear in Trash

I formatted a 1 TB Apple drive to OS Extended Journaled w/ 2 Partitions and put it into a USB HD case and plugged it into my 4th Gen Airport Extreme model A1354. I enabled File Sharing and put it into Bridge Mode (because the ethernet WAN goes to my D-LINK DSL modem/router). The HD mounts on my OSX 10.6.8 machine.

When I Trash a file, it does not appear in the Trash folder. I have not worked with external drives since System 9.5 and I don't remember why the files don't appear in the Trash folder, so I can drag them out again. IIRC it goes to an invisible trash folder.

1) How do I make the files appear in the Trash so I have an opportunity to drag them out before Emptying?

2) How exactly does the Trash Folder work -- is there a different folder for every HD? Is the Trash Folder(s) located on the Startup Drive or is there a Trash Folder located on every drive? I've never used a computer that has more than one internal drive.

It would be useful if the Trash folder created a sub-folder for every HD and kept the files segregated.