by Slim and Gabby » Sun Oct 05, 2008 9:35 pm
If it's really old, it may have been used for rendering whale-blubber; in the old days of mercury mining, they would use them to hold the huge amounts of quick-silver before decanting.
If you want a great way to season something big, you may want to heat it up on a big out door propane burner/stove; heat it slowly at first, then turn the heat way up and spray it with salad oil till it smokes. Eventually it will turn black, turning into an "enamel coating"; this kind of coating is bullet-proof and will take a pretty good scrubbing when you clean it. I "bullet-proof" all my cast iron like this and I never have a sticking problem. I got my Mom's 1910 Wagner Ware waffle-iron, it has a beautiful gloss-black enamel patina that's hard as a rock and cleans up with a stick. Her old griddle has a pretty amazing one too, but it's not shiny, but non-stick all the same.
If it's cracked, just take it to a shop and have the sucker welded, a competent welder should be able to fix it for you without much fuss. The weld will give it character too, and people will know "It aint no sissy kettle!"
Slim