Thirty days hath September

I raised my hand at this point and said, “Mrs. Watson, I know mine already. Thirty days hath September, April, June, and November. All the rest have thirty-one, except February. It has twenty-eight, we find, unless it’s leap year: Then it has twenty-nine.”

The days of the month Thirty days hath September, April, June, and November; February has twenty-eight alone, All the rest have thirty-one, Excepting leap-year, that's the time When February's days are twenty-nine.

She did not even think it permissible to say: "Thirty days hath September, April, June, and November."

"Multiplication is vexation," a painful reality to schoolboys, was found a few years ago in a manuscript dated 1570; and the memorial lines, "Thirty days hath September," occur in the Return from Parnassus, an old play printed in 1606.

Others held to the astronomical year and adopted a system of conventional months, such that twelve of them would just make up a year, as is done to this day in our own calendar, whose months of arbitrary length we are compelled to remember by some such jingle as the following: "Thirty days hath September, April, June, and November; All the rest have thirty-one Save February, Which alone hath twenty-eight, Till leap year gives it twenty-nine."