Before getting back to detailed newspaper descriptions of leap year balls, here's a less detailed but still useful description of one in the form of a very mediocre poem.  It was published on page three of the Oakdale Leader, in Oakdale, California, on Friday, February 14th, 1896.  

The leap year elements mentioned specifically in the poem are:

• the ladies "managing" things and taking the author into the ballroom
• the "beaux" sitting in a row waiting for partners and the ladies rushing to find one, making sure no one was left out
• Fannie and Julia as some sort of ball organizers or floor managers, wearing badges and making sure things went smoothly
• a lady acting as treasurer and, by implication, asking the author to dance

I admit to cynically feeling that the ladies being concerned that none of the "gints" were slighted was showing more care for their feelings than many gentlemen showed for those of ladies when in conventional roles -- the ladies were perhaps deliberately setting an example for the gentlemen of how they wished to be treated....[a few comments and a bad poem behind the cut]