In my ongoing project of composing six small preludes, this one was very difficult to write for me  and I am not very satisfied with the result. Basically, it is a canon from measures 1-11 with the upper voice leading, and and then a canon from measures 12-30 with the lower voice leading. M. 1-6 and 12-17 are virtually identical with the voices just exchanged and once in the tonic, then in the dominant (double counterpoint). The tonal plan is C Major -> G Major -> e minor -> G Majo