Anyone who has driven up to UCSC has probably wondered about the rock ruins with arched doorways near the Barn Theater. Pagan temples, perchance? Ohlone sweat lodges? Actually, as discussed in an exemplary new work of local history, they are lime kilns, reminders of one of Santa Cruz County's major industries in the late 19th century.

In Lime Kiln Legacies, a raft of authors--Frank A. Perry, Robert W. Piwarzyk, Michael D. Luther, Alverda Orlando, Allan Molho and Sierra L. Perry--detail the history of the lime kilns dotted throughout this county, from UCSC to Adams Creek, Pogonip, Liddell Creak and points north in the Felton area.

Before it was supplanted by Portland cement, builders relied on lime to make mortar for brick buildings. The Spanish used lime in our mission, but the demand really skyrocketed after the Gold Rush (as it did for the timber in this area, too). Local limerock was quarried, burned for several days at controlled temperatures, then hauled to building sites and mixed with sand and water.

Lime Kiln Legacies, like the best local histories, thrives on detail and minutiae. The diagrams and photos here allow even the novice to understand the difference between pot kilns and continuous kilns. The authors pay due tribute to the expertise of the kiln workers, who had to judge the exact temperatures of their kilns without precise instruments: "If there was a light haze of smoke above the kiln, this was good. Black smoke meant that the fire needed more air. If the air above the kiln was clear or flames were visible, the fire had too much air and the draft had to be reduced." It could take as long as five days to properly cook a load of limerock, and the fires had to be watched around the clock.

An exhaustive rundown of the lime companies in Santa Cruz County includes much fascinating information about Henry Cowell, whose mining and ranching wealth eventually benefited UCSC. A controversial figure ("ruthless, tightfisted capitalist" or "wealthy visionary and conservationist"? You decide), Cowell amassed land and fortune with great success in the 1800s, at one point gaining control of almost the whole of Main Beach. In the early 20th century, troubles beset Cowell. He was winged by a neighbor angered over a boundary argument. His daughter, Sarah, died in a buggy accident on the ranch. His son Ernest V. died suddenly of meningitis.

In addition to many evocative photos, the book also contains information on where to find lime kiln remains in the county, a walking tour of the lime ruins at Bay and High streets, a discussion of all the ways (horse cart, rail and ship) that lime was moved to market, a list of lime-related place names and a very impressive bibliography.

Lime Kiln Legacies: The History Of The Lime Industry In Santa Cruz County, Museum of Art & History, 253 pages; $24.95 cloth. The museum will host a booksigning party and reception on June 2, 1-3pm, in its auditorium. (831.429.1964)

Send a letter to the editor about this story.