mac book as an external hdd?

I have a mac book air and am running out of hd memory but have 180 spare gb on my old black mac book - is there a way I can transfer (my itunes purchases tv series particularly) from my air to the mac book - I have connected the two up by ethernet and nothing!

all help gratefully received

Are they both connected by ethernet cable via a router or switch? or just a single cable?

If it's a single cable you'll need to use a crossover ethernet cable (they are wired differently to standard ethernet patch cables).


edit: that said, depending on the age of your Macs you can use a non-crossover ethernet cable as newer models can auto switch.

Either way make sure you have file sharing enabled in system preferences.

black mac book is 2007
mba is 2009

I have a single ethernet between the two -

would prefer not to have to get extra cables - would it help if I connected them both by ethernet to my time capsule?