Last week of touring around Toronto was too much for the little cart that I bought to haul around my oxygen. Apparently thumping repeatedly over the curb was too much for the wheel to handle. It started to crack two weeks ago but I could always shove the tire back on the plastic bit but last week it gave up the fight for good. Isaiah tried gluing it together but that only lasted for a few hours. Turns out a 15$ cart from Chinatown can only handle so much abuse.
I guess it's back to carrying oxygen in the backpack until I get a replacement.
As a random person in the elevator observed, 'looks like I have a wheel problem.'