Imagine a metal rod heated in a controlled setting, with other relevant conditions held fixed. Under those stipulated conditions, heating makes the rod expand.
Minor premise: This rod was heated under those conditions.
Major premise: Such heating causes rods of this kind to expand.
Conclusion: This rod expanded.
Heating is both the evidential middle term and the real explanatory cause. The case illustrates the cause-to-effect orientation characteristic of limmī demonstration, provided the premises are suitably established.