My dear readers will know I'm mentioning this auction because I already have a copy of this book, also gotten on eBay.
It is the 1811 Bennington, Vermont pirated or "surreptitious" edition of Hosea Ballou's Treatise on Atonement, following the first edition of 1805. It makes a fun read, though I admit I've only skimmed through a few pages. The last printed edition (of 1986?) was derived from a later, more moderate edition so this copy is worth having if you're keen on knowing more about Ballou.