The first written premise is not automatically the major premise. The subject of the conclusion identifies the minor term and its predicate identifies the major term. We then assign the two premises accordingly.
Example:
Every teacher is human.
Every calligrapher is a teacher.
Therefore, some humans are calligraphers.
Here “human” is C, “calligrapher” A, and “teacher” B. The first statement is the minor and the second the major in this chosen conclusion, regardless of their order on the page.