using different amp hour ratings will work as far as powering your gear goes, however, the 1.6 aH batteries will be drained by the 1 aH as the 1 aH will try to charge itself from the higher capacity. This will result in an overall decreased battery life.
Better to stick to the same amp hour when wiring in parallel. Get yourself another 1.6 and you'll be in business.
Even though rowjimmytour's questions have been answered, I want to provide a useful tip in this kind of situation.
When using batteries in parallel, it's a good idea to insert diodes into the + leads of each battery. Even if they are the exact same batteries, you should do this (because "identical" batteries are never identical in behavior). As you run batteries, the voltage levels will change between the batteries. Without diodes, the higher voltage batteries will drain into the lower voltage batteries. The diodes will prevent that from happening. One thing to keep in mind, though, is that diodes generally have a small voltage drop, so if what your trying to power is picky then that could be a problem.
Food for thought.