Hmmmm... no jumper typically means drive is set to "Master"...

In Linux the Master drive on the first IDE channel is designated as /dev/hda and the Slave on the first IDE channel as /dev/hdb. Master and Slave on the second IDE channel are /dev/hdc and /dev/hdd respectively.

On a MkI you have two IDE cables (or at least 2 IDE headers, the MkI, unless it was a dual drive unit from start, only came with one cable), each with just one contact - the drives should both be set as Master and recognized as /dev/hda and /dev/hdc)

(Note: the MkII and MkIIa, that only have one IDE channel available, cheats a bit in order to be compatible with the MkI, and actually calls its Slave (on the first and only IDE) /dev/hdc)

/Michael