Canning chokecherry jelly is a risky operation involving lots of glass jars, fire burning from multiple stovetop elements (gas elements on my stove) and scalding liquids (lots of boiling water and the cooked jelly liquid itself). So chances of sustaining severe burns are significant if careful attention is not paid during every single step of the process. I've been canning jelly for fifteen years using the same steps each time now without ever getting burned.
But yesterday's canning session nearly ended that winning streak when the bottom of a jar just filled with hot cooked jelly liquid broke away as I was tightening the lid before placing it into the canner for the final boil. Fortunately, I always use a fairly heavy hand towel to firmly grip the jar top and bottom while tightening the lid, and that towel shielded my left hand from both a potentially deep glass cut and a severe scalding.
The jar cracked sometime during the initial boiling step to sterilize it and I didn't notice it before filling the jar. A close look before ladling in the hot jelly would have revealed the crack. But I didn't look first, trusting my process too much to think anything could go wrong.
I filled it, eased the lid on, picked it up using the hand towel to get a firm grip on top and bottom and then applied quick rotational pressure to tighten the lid down. There was a faint pop, then scalding hot jelly liquid poured out of the now bottomless jar onto the stovetop.
Y I K E S is not the word I uttered at that moment in time.
I quickly tossed the two pieces of broken jar and the still-hot jelly-soaked towel into the sink to avoid being burned, leaving a puddle of jelly on the stovetop and a messy trail of the hot stuff splattered across the countertop to the sink. Staring at the mess I cursed some more then breathed a sigh of relief at avoiding injury.
So I've added two more crucial steps to my canning process which were not included before this incident: 1) carefully inspect each jar as soon as it is removed from the canner after the sterilizing boil and 2) carefully inspect each jar once more before tightening down its lid.