The Fiery Furnaces made their debut in 2003 with the mesmerizing Gallowsbird's Bark, which promptly slipped through the cracks before regaining steam earlier this year. Lead singer Eleanor Friedberger's nonsensical prattle sizzled atop eruptions of chortling twin guitars, epileptic piano and pumping synth. But on Blueberry Boat, Friedberger and her brother Matthew decided to put last year's good-time-on-the-psych-ward boogie through the ringer. The result will be labeled "difficult" by some and "ambitious" by others. Songs stretched to frustrating lengths are filled with piano-recital sludge, keyboard noodling, Matthew's snot-nosed singing and--in the case of the opener, "Quay Cur"--distracting, garish electronic muckery. But despite these faults and an initially glaring lack of forward momentum, the album works by easing you into its odd rhythms like a Thomas Pynchon novel. Whereas Bark felt like a race to the rare-books store, Boat resembles a swampy, scatterbrained lope. There are fewer grease-fire guitar jags--which increases their value--though the lyrical scenarios are as ludicrous as ever, discussing as they do a lost dog that finds God and pirates who seize a ship laden with Grand Rapids blueberries. Both Friedbergers persist, à la the RZA, in pushing lyrics a line or two past where the limits should be, but now the calculated, gratuitous sloppiness seems a virtue.