eth0 or eth1? Not a problem but a puzzlement

[Cybe R. Wizard]

Anytime I reboot my box it's a toss-up as to which will contain my
connection to the internet, eth0 or eth1.  Sometimes it's one,
sometimes the other.  I can't for the life of me figure out why nor how
to cause it to be one or the other.  
Any ideas?  Any more data that I could/should supply?

Cybe R. Wizard
-- 
Nice computers don't go down.
	Larry Niven, Steven Barnes
		"The Barsoom Project"