I think 35mm film is actually 35mm wide, measuring edge to edge. Remember the original 'full frame' was for motion picture, which runs the film through vertically, so the frame there wasn't even 24x36mm. Wiki has many more details than this I'm sure.
Have fun with the camera.
Perhaps you're right. And if you are, it just illustrates how inconsistent the format naming is
"Often moments come looking for us". - Robert Frank
"Make good art!" - Neil Gaiman
"...the heart and mind are the true lens of the camera". - Yousuf Karsh