In the spirit of Alec's pedentry, I must mention that lube does not work by making things moist, instead it works by reducing friction and preventing direct contact between solids. Oil based lubes are a prime example of this as they contain very little water and therefore is ineffective at making things moist but is still effective at reducing friction. Water by itself is actually a pretty bad lube.

Also we're talking about machine lube right? ...right?