Looked.thru.Dan.Holohan's."Lost.Art.Of.Steam.Heat"....in.it.he.relates.a.bit.o f.radiator. history,but.it's.all.pre-20th.c. Get.in.touch.with.him.at:www.danholohan.com He's.got.heating.history.for.blood.and.it's.a.good.bet.that.he.will.know.the.P erfection. Good.luck....and.let.us.know.what.you.come.up.with! John.Mascaro