Thursday, May. 23, 2019

Marin’s Mysterious Olema Lime Kilns

By Richard Nielsen · November 29, 2017

At the Lime Kilns, c.1900,  photograph by Gertrude Southworth, Courtesy of Bolinas Museum, Southworth Archives. <span>&copy; Bolinas Museum </span>

At the Lime Kilns, c.1900, photograph by Gertrude Southworth, Courtesy of Bolinas Museum, Southworth Archives.

Olema Lime Kilns, 1953, per illustration in Treganza's article in "Geological Guidebook to San Francisco Bay Counties." <span>&copy; CA Division of Mines </span> Olema Lime Kilns as they appear today. <span>&copy; Richard Nielsen </span> Close-up of the entrance to Kiln #2. <span>&copy; Richard Nielsen </span>

The Olema lime kilns, located just west of Highway 1 between Olema and Bolinas, have long aroused curiosity and spawned numerous theories.  For over a hundred years visitors to the kilns have been scratching their heads.  However, we can now finally dispel many of the old myths, including the myth that the kilns are of Russian origin. 

In San Francisco’s early years, almost as soon as buildings were erected, the City was beset by fires that quickly devoured the wooden structures.  The need for fire-resistant brick edifices required both brick and lime mortar.  Early on, builders sought local sources of limestone.  Though they found some sources close to San Francisco, most had limited potential. By 1850, one source was uncovered on the east bank of Olema Creek.  Most likely, local wood cutters happened upon the limestone as they cut down the forests of the Olema Valley to supply firewood to San Francisco’s ever-growing population.

The Olema source consists of Calera limestone in Franciscan rock which was formed from sediments on the ocean’s bottom.  This type of rock is abundant in Marin’s landscape. The rock formed from these sediments is now primarily located east of the Point Reyes Peninsula.  The Point Reyes body of limestone was likely offset from a much larger limestone deposit in the Santa Cruz area by movement along the San Andreas Fault.  

Kilns are used to heat limestone to produce lime.  The three kilns in Olema may have been erected in two phases.  The smaller one on the right, designated Kiln #1, appears to have been built first and likely provided lime for the construction of the two larger kilns and the storage area on the left side of the complex.  Highly fractured limestone from the bluff above the rear of the kilns would have been easily removed and loaded into the top of the kilns.  At the time of abandonment, Kiln #1 was loaded with limestone and remains so.

By 1850, two Forty-Niners from Maryland, physician James Shorb and farmer William Mercier, negotiated a ten year lease with landowner Rafael Garcia to exploit the Olema Valley limestone.  Terms of the lease allowed the two men to build kilns for lime production, one third of which would be delivered to Garcia according to their contract.  During that same year, Shorb would become the first county judge, and Mercier would become the court clerk.  Construction of the kilns was initiated in late 1850 and likely at least partially completed by spring of 1852.  Significant production didn’t occur until the summer of 1853.

At the time Adan E. Treganza’s article appeared in the 1951 Geologic Guidebook of the San Francisco Bay Counties, archeological evidence indicated that the kilns had probably been fired no more than a dozen times.  A provision in the lease indicates that the lime would be sent to the Embarcadero (most probably referring to Bolinas) by ox cart, from whence the lime could easily be shipped to San Francisco.  Treganza concludes his article by saying: “That lime from the kilns ever reached San Francisco or any other destination is, however, unlikely, for only a brief period of operation is indicated, which probably resulted in considerable financial loss to the original builders and operators.”

While it’s uncertain exactly when they began to produce lime by burning limestone, it’s clear that they began shipping the lime by August 29, 1853.   According to the Maryville Daily Herald, on that date the sloop Curlew carried a shipment of lime to San Francisco.  A final shipment was made on November 14 on the sloop Mary.  Over 320 barrels were sent to San Francisco between those dates.  Based on the requirement that one-third of the lime be provided to Rafael Garcia, at least 500 barrels of lime were likely to have been produced, which would far exceed the twelve firings hypothesized by Treganza.

Two factors likely brought about the demise of the Olema lime kilns.  Increasingly, larger quantities of lime were reaching San Francisco from an abundance of limestone near Santa Cruz.  But a more serious factor appeared in an article in the October 15, 1853, issue of the Sacramento Daily Union, which stated: "Day before yesterday a small boat containing five men, in crossing the bar at Bolinas Bay, was capsized and five of the number drowned. The names of those recognized were Benj. Stinchfield, Frederick Lewis and John Williams; besides two Frenchmen, names unknown. They had been working at a lime kiln at that place."  The loss of skilled labor was undoubtedly the death knell for the Olema operation.

Further, the failure of their effort to establish a productive source of lime contributed to the departure of both Shorb and Mercier from Marin by the fall of 1855.  Both of them returned to their families which they had left behind in Maryland. However, the remains of their lime kilns remain as a monument of enduring interest.

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Recent Comments



Katherine Duke wrote over 1 year ago

Thank you !


Dorsey McTaggart wrote over 1 year ago

Quite interesting.  Once again.  Thank you for these newsletters.


Laurie Thompson wrote over 1 year ago

Thanks for your interest, Dorsey!

The credit goes to the author, Richard Nielsen.

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