The first was the 1933 Sons of the Desert, as sexist and dated a piece as you could ever want to see, Sugar. I can't find this online, though there's a severely edited version here. The New York Times says,
Let it be said at once that the new Laurel and Hardy enterprise has achieved feature length without benefit of the usual distressing formulae of padding and stretching. It is funny all the way through.
DVDTalk reviews this disk, calling both County Hospital and Busy Bodies "inspired". County Hospital is from 1932. I can't find it online, but somebody has put the first half of Busy Bodies (1933) at youtube today:
My guess is that part 2 will soon follow.
I found all 3 of these to be slow and labored.