The property of a testator, except as otherwise specially provided in this code and under civil procedure, must be resorted to for the payment of legacies in the following order:
1. The property which is expressly appropriated by the will for the payment of the legacies.
2. Property not disposed of by the will.
3. Property which is devised or bequeathed to a residuary legatee.
4. Property which is specifically devised or bequeathed.