While Polygram staffers were digging up master tapes in their vaults for their remastered reissues of Graham Parker's first four studio albums, they ran across something they didn't expect to find (a startlingly common event when labels start looking through their tape libraries) -- a set of solo acoustic songwriting demos Parker had recorded about a year before his debut long-player, Howlin' Wind.

That's When You Know compiles 15 songs from these demo sessions; three of them would pop up on Howlin' Wind and one would later appear on Stick to Me, but this release marks the first time most of the other 14 songs have been heard in public in close to 25 years.

In his liner notes to the set, Parker (often his own harshest critic) claims to have entirely forgotten six of the songs, and describes his initial reaction to hearing the tapes again as "Ouch! Ouch! Ouch! Doh!" To be certain, not everything here is top-shelf material; the acoustic demo of "The Raid" only confirms that the song works a lot better fast and loud, while "Stargazer" and "Sunny Side Down" support Parker's assessment that he was still purging himself of his folkie tendencies.

But if Parker wasn't yet the R&B-fueled demon of his finest work, he was a strong songwriter with a commanding vocal presence; even the lesser material is engaging, while "Hole in the World," "Express Delivery," and especially the title cut are more than worthy additions to Parker's catalog.

These demos are Parker's equivalent to Elvis Costello's oft-bootlegged recordings with his first band, Flip City -- juvenilia that lends a fascinating perspective to the artist's early work, and pretty good listening on their own terms.

As a bonus, Polygram has also included Live at Marble Arch, a frequently bootlegged 1976 live in the studio session with Parker and the Rumour impressing a captive audience of U.S.

Polygram staffers, assembled in hopes of winning the band an American record deal.

(Mercury took the bait, but listen to Parker's 1979 song "Mercury Poisoning" for a perspective on how things worked out.) Dominated by material from Howlin' Wind and some revved-up R&B covers (including an incendiary take of "Chain of Fools"), Live at Marble Arch captures the early Rumour at the top of their form, and if you want proof that Graham Parker was one of the most exciting acts to come out of the late pub rock/early new wave scene, this disc will do nicely.