California brick
CALIFORNIA BRICKS


T.W. Petersen & Company, Lick Observatory

History

Theodore W. Petersen, born about 1835 in Holstein, Germany, started brick manufacturing in San Jose, Santa Clara County, California, in 1881. His brickyard was located on Keyes between 3rd and 4th streets, San Jose. In 1881, Petersen was awarded the contract by the Lick Trustees for supplying brick for the new Lick Observatory and buildings atop Mount Hamilton, located 13 miles east of San Jose. Lick Observatory

James Lick, who had made a fortune in real estate following the Gold Rush of 1849, had bequeathed a large part of his fortune to the construction of an astronomical telescope and observatory that was to bear his name on Mount Hamilton in 1874. James Lick died in 1876, long before the completion of the observatory, and his remains were interred in the basement vault of the main observatory building.

Lick's confidential agent, Thomas E. Fraser, was made the superintendent of construction and the foundation work began in 1880. The observatory and supporting buildings were to be constructed of red brick. But it became immediately apparent that hauling large quantities of building material up 4,200 feet on a narrow wagon road was going to be a slow and expensive proposition. It was initially estimated that it would have cost $9.00 per thousand bricks, plus $22.50 per thousand, to haul the bricks from San Jose. Fortunately, during the foundation work, Fraser had discovered a clay bed suitable for manufacturing bricks about a half mile west of the observatory site. This clay was sufficient to supply all the brick necessary for the construction.

At the present site of the helicopter pad, one-half mile east of the observatory, was where Petersen dug clay for bricks and fired them in field kilns. Fragments of white quartz were added to the clay as grog. Sand was hauled from Smith Creek, six miles away, to temper the clay. The bricks were sand-molded in wooden molds, sun dried, and fired in field kilns. Laborers from Petersen's main brickyard on Keyes and Third streets in San Jose were brought to the mountain top to work. Most of them were Chinese laborers directed by Henry Stammer, a German foreman and brickmaker.

Petersen's crew made 2,600,000 red common bricks at a cost of only $13.50 per thousand, saving over $46,000 in haulage expense. Most of the brick buildings were completed by 1884. The buildings were painted white to protect them from the weather. These early Petersen bricks can still be seen today in the walls of some of the older buildings still standing. The clay pit was abandoned after the completion of the construction.

In later remodeling work of the existing observatory buildings, Livermore buff face brick and red San Jose pressed brick were added. Petersen died on March 10, 1902, San Francisco.

Site of Petersen's clay pit and kilns
View of the site of Petersen's clay pit and brick kilns at the helicopter pad.

Petersen's Lick Observatory Brick

Common brick is pale orange to pale orange red, mottled with light and dark patches. Sides display faint yellow flash, stack indents, transverse markings, and an irregular lip around the top on some. Bottom face is smooth and flat, with occasional pits. Top face has a rough, irregular surface, highly pitted and abundant visible clasts, with longitudinal strike marks. Edges are sharp but often broken and irregular. Corners are rounded or broken. Interior clay body contains about 40 percent clasts of angular to subangular shale, red chert, and quartz, up to an inch across. Clay body itself is porous. This brick was made using the sand-molded, soft mud process, between 1881 and 1884. Length 8 3/8, width 3 3/4 - 4, height 2 1/4 inches.

Petersen brick
View of the sides of Petersen's common brick made at the Lick's Observatory.

Petersen brick
View of the bottom face of Petersen's common brick made at the Lick's Observatory.


Petersen brick
View of the top face of Petersen's common brick made at the Lick Observatory.


Petersen brick
View of Petersen's common brick made at the Lick Observatory showing the quartz grog.


Petersen brick interior
View of the interior of Petersen's common brick made at the Lick Observatory.


Petersen brick interior
View of the interior of Petersen's common brick made at the Lick Observatory.


Microscopic view of the interior clay body of Petersen's common brick made at the Lick Observatory (50x, field of view is 1/4 inch).
Microscopic view of the interior clay body of Petersen's common
brick made at the Lick Observatory (50x, field of view is 1/4 inch).


References

Brick and Clay Record, April 1902, p. 183.

Federal Census Records, 1880.

Laffey, Glory Anne, Nineteenth Century Brick Making in Santa Clara County, San Jose State University Geography Report, 1980.

Mining and Scientific Press, June 23, 1888, p. 393-417.

San Jose City Directory, 1881-1882.

San Jose Mercury News, S.J. Builder of Observatory Dies, February 5 ,1928, p 15.

Stolp, John E., written communications, 2007.

University of California Observatories, Lick Observatory, 2008, http://mthamilton.ucolick.org/ (accessed 2008).

Copyright 2008 Dan Mosier

Contact Dan Mosier at danmosier@earthlink.net.