Networking an external hargrove

I have acquired a La Cie external hard drive with Firewire 400 and 800 and eSata connections. To use it for backing up Time Machine at present I am connecting it directly to my Mac Air using a Thunderbolt to 800 cable. Is there a way I can connect the hard drive via the 800 port to my router so can back up without physically connecting it every time? Thanks for any suggestions.