What's where at Lick Observatory on Mt. Hamilton

Under Construction!

Sites of Instruments (and other relevant structures)

This is a list giving the history of many of the sites on Mt. Hamilton.
Small Dome
The small dome was completed in 1881 and the 12-inch refractor was mounted in October. [PLO I, 45 (1887)] In 1979 the 12-inch was replaced by the 40 inch Anna Nickel reflector. [J. Osborne, Sky & Telescope 60, 97 (1980)] The USC&GS first began observing the top of this dome as a triangulation intersection point in 1883. Holden provides two sets of early correspondence from the USC&GS about its location. [PLO I, 175 (1887)] [PLO I, 307 (1887)] The geodetic agencies have always designated it the ``Small Dome'', and it currently has NGS PID = HS4865. More recent observations held by NGS give its precise position. [NGS Data Sheet]
Small Dome Eccentricity
The small dome cannot itself be occupied by a surveying instrument. To permit occupation a standard brass benchmark disk was installed in the ground just to the west of the dome in 1922 or before; its first recorded occupation was in 1923. This currently has NGS PID = HS4863 and has recently been occupied as part of a GPS-based survey. Consequently the location of this point is known better than any other spot on Mt. Hamilton. The eccentricity to the small dome is known precisely and is in the NGS database. In 1947 the USC&GS set a number of other reference marks around the original benchmark. [NGS Data Sheet]
Brick and Cement Water Tank on Kepler Peak
This site is about 48 feet higher than the leveled top of Observatory Peak. This water tank was built in 1882 to provide water pressure to the main building. [PLO I, 42 (1887)] It had fallen into disrepair long before the early 1980s and contained only detritus with various insect and reptilian life forms. It was refurbished with a new concrete lining and roof to hold water again in the early 1990s. Its existence is relevant only because of the later construction of the 24-inch dome adjacent to it and the cartographic confusion of all the circular structures on Kepler Peak. See entry for the Purple Dot.
Original Huyghens Peak Water Tank
The first Huyghens Peak water tank was built in 1883. Its original water source was from the catchments on Observatory Peak. [PLO I, 43 (1887)] It is visible in early photographs and cuts. It was situated on the north slope of Huyghens less than halfway up from the original road to the top of the peak. A windmill stood next to it and provided pressure to pump water back up to Observatory Peak. [PLO I, frontispiece (1887)] It was apparently moved within about a decade, for photos from the 1890s show a tank located at the top of Huyghens Peak and still accompanied by a windmill. This is consistent with its current location. [PASP 7, 249 & 250] Photos from a scrapbook show that in the 1920s there was a residence on this site. The current alignment of the roadway has been moved notably to the south so that it makes a significant cut into the north slope of Huyghens Peak. There is no trace of the original tank or the residence.
Huyghens Peak Water Tank
Photos from the 1890s show a tank located at the top of Huyghens Peak and still accompanied by a windmill. This is consistent with its current location. [PASP 7, 249 & 250] Between 1950 and 1955 the Tauchmann Dome was built atop it. [Painting in Mt. Hamilton Diner]
The Heliostat for the Photoheliograph was due south of the Fauth Transit. The distance from the center of the Transit House to the Heliostat was approximately 25 feet. [PLO I, 34a (1887)] The site of the Heliostat must have been destroyed by 1907 when construction began on the new Photographic Laboratory and Plate Archive.
Original Photographic Laboratory and Photoheliograph
The original Photographic Laboratory was south of the Fauth Transit and the Heliostat. The distance from the center of the Transit House to the Photographic Laboratory was approximately 70 feet. [PLO I, 34a (1887)] The Photoheliograph was located within this building, and it was connected to the Heliostat by a long tube. [PLO I, 39 (1887)] In the 1890s the requirements for temperature stability brought forth another photographic laboratory in the basement of the Meridian Circle building. [MLSA Ann. Rep.] The site of the original Photographic Laboratory must have been destroyed by 1907 when construction began on the new Photographic Laboratory and Plate Archive.
Large Dome for the Lick 36-inch refractor
The brick work of the Large Dome was completed in 1886. [PLO I, 43 (1887)] Since 1963 this dome has been an intersection point for triangulations by NGS. Its position can be found as NGS PID = HS4868 where it is designated ``South Dome''. [NGS Data Sheet] After the 1984 Morgan Hill earthquake the brickwork and mortar of the dome showed notable buckling. By 1985 its condition was deemed hazardous. In 1988 the outer layer of bricks of the large dome, and the entire main building, was replaced by steel-reinforced concrete. There is some chance that the centering of the dome may have shifted by a few inches as a result of the decay and renovation.
Transit House
In [PLO I, 175 (1887)] Holden chose to specify the Fauth Transit as marking "the coordinates of the Lick Observatory". The USC&GS [Schott 1900] used its position as marking the definitive longitude on Mt. Hamilton. When calculating the positions of other structures on Mt. Hamilton Klemola has presumed that the published position for Lick Observatory in the 1957-1980 AENA refers to the Fauth Transit.

During the 1950s a structure in roughly the same location was used as the Post Office. The entire site was obliterated about 1956 by the new northeast wing of the main building which contains the current Post Office.

Meridian Circle House
The Meridian Circle House was completed in 1884. Holden gives a detailed description of its layout. [PLO I, 38f (1887)] This building appears to be marked on the 1955 USGS 7.5' TOPO. In the early 1950s George Herbig occupied the office at the east end of the structure. It was demolished about 1956 and replaced by the new northeast wing of the main building which contains the current Post Office.
Meridian Circle South Mire
Holden reports that this was located about 80 feet south of the Meridian Circle House. [PLO I, 34a (1887)] In 1885 an iron house was built around it. [PLO I, 43 (1887)] Tucker reported that the mire was a small hole in an iron pier located 97 feet south of the Meridian Circle itself. [PLO IV, 12 (1900)] The south mire house can be seen in numerous photos and it remains in existence today. The site map indicates that the structure may currently be in use as a transformer vault. This structure is the only remaining evidence of the Meridian Circle on Observatory Peak.
Meridian Circle North Collimator Hutch
Shiloh Unruh reports that he has found the ruins of this structure many miles north off Kincaid Road.
6.5-inch Clark Refractor Dome
Warner and Swasey constructed a portable telescope upon which could be mounted the lens from the south collimator of the Meridian Circle. Circa 1887 a dome for this telescope was constructed south of the Meridian Circle. [PLO I, 65 (1887)] [HBLO 44-46 (1888)] The UCO/Lick Obs Instrument Lab has photo showing this dome partly obscured by the original Old Dormitory. The brickwork of the Large Dome is complete, but its dome is under construction. [(1997)] Photographs dated from 1888 to 1908 show this dome located just east of the Main Building near where the southern road ramp coming up from the original Old Dorm intersected with the plateau. [PASP 7, 249 & 250 (1895)] This dome is not evident in photos from the 1930s. [PASP 43, 412 (1931)] [PASP 47, 89 (1935)] Note that in 1992? the courtyard to the east of the Main Building was renovated and a cuppola was built over a bust of the Rev. Laurentine Hamilton. The position and size of this cuppola very nearly match that of the dome from the turn of the century, but the similarity is purely coincidental.
USC&GS Transit Sites
In 1888 the USC&GS setup a station on Mt. Hamilton to complement the triangulation data for the Small Dome. Using a local survey for the eccentricity, the position of the Transit House was published simultaneously. [USC&GS Bull. 13 (1899)] During the observations the latitude transit was determined to be defective, but the value was consistent with Tucker's Meridian Circle observations. The latitude station was 3.51 arcsec N and 16.36 arcsec E of the Fauth. Curiously and sadly, a footnote indicates that the USC&GS had no idea that the Fauth Transit and Meridian Circle were two distinct instruments. Thus, beginning in 1900, the published record of positions begins to confuse those two sites. [USC&GS Special Pub. 4, 714 (1900)] In 1891 T.C. Mendenhall performed a gravity measurement for the USC&GS; we may presume this was done on one of the transit piers. [USC&GS Special Pub. 40, 179 (1917)] S. Beall published a summary of all of these astronomical observations along with a detailed site description. There were two piers separated by 2.019 meters. The east pier held the latitude transit, and the west pier held the longitude transit. [USC&GS Special Pub. 110, 145 (1925)] From the relative positions of the USC&GS and Fauth transits it becomes evident that the USC&GS transit piers were located a few meters northwest of the subsequent site of the 20-inch Astrograph Dome. It appears that all trace of these piers was obliterated by the Astrograph.
Old Crocker Dome
This dome was constructed in 1891. [PASP 2, 128 (1890)] The dome housed the Crocker telescope, and a number of the other small lenses which were used for wide-field galactic photography. [PLO XI (1913)] The dome can be seen in aerial photographs of the mountain. [PASP 43, 412 (1931)] The dome had apparently been unused after Barnard left Lick.

Merle Walker believes he has photographs showing the dismantling of this dome in the same frame as the construction of the Shane Dome (mid 1950s), and says the dome was given to a farmer in the back country. Shiloh Unruh corroborates this saying that its new home is on the Scotts property somewhere off Kincaid Road.

As of 1996 the only remaining evidence of this dome is a brick circle with a rectangular depression and a grounding cable to its north.

18-inch Schaeberle reflector site, 1895
Mentioned as being about 1000 feet east of the Large Dome but not visible in the foreground of a photo apparently taken from Kepler Peak. [PASP 7, 228 (1895)] Given the amount of subsequent development in that region of the mountain its precise position cannot be determined without a photograph.
Unknown Dome near Campbell House
Dave Lingo has gathered a large collection of early photographs of Lick Observatory. These photos have been cataloged by Shiloh Unruh and are currently in the hands of Rem Stone. One photo shows a telescope between the Director's house and the Crossley. This dome is just south of the highest point on Ptolemy Peak such that it stands above the height of the Director's house. Campbell was already residing in that house in 1895. [PASP 7, 228 (1895)] The Crossley Dome was finished in 1896, and the director's house was enlarged by Campbell about 1910. Don Osterbrock recalls that a visiting observer who was using the Crossley circa 1910 slept in an empty dome near the Crossley.

As of 1996 the site consisted of rough ground covered by short grasses and small oak trees. There was a piece of drain tile and a brick, but no other trace that a structure had been there.

The Crossley Dome
Construction began in 1895. The dome and telescope arrived in 1896. [PASP 7, 197 (1895)]
Photographic Laboratory and Plate Archive
Initial funding for this structure was acquired in 1905. Construction of one half took place in 1907, and the second half in 1909. Its intent was to be fireproof (and presumably earthquake-proof); it is a steel-reinforced concrete structure. [MLSA B&G] Its construction must have seriously obstructed the southerly view of the Fauth Transit. It is visible in aerial photographs taken in 1931. [PASP 43, 412 (1931)]
Bamberg Transit Pier
The Bamberg Transit was setup for participation in the first and second international campaigns of longitude. It was setup east of the Meridian Circle. [BIH, 2aOIL 7, 673 (1941)] A photograph taken in 1934 shows a hutch which is located at the correct longitude. It is between the Meridian Circle and the bridge to the Old Dorm, near the north edge of the Observatory Peak plateau. [PASP 47, 89 (1935)]
Double Astrograph Dome
Archival files from Vasilevskis in the AME laboratory contain copious photographs showing the construction of this dome. Klemola maintains these files.
Concrete Pad SW of Double Astrograph
Gene Harlan poured this pad in the mid-1960s. It supported a wooden clamshell structure which housed an 8-inch f/1 Schmidt camera on loan from Zwicky at Caltech. This was used as part of a supernova patrol. The clamshell is visible in the 1977 aerial survey photos.
Shane Dome
Construction of this dome began in the early 1950s. It obliterated the Mt. Hamilton tennis courts, which extended to the west of the Shane Dome site. Since 1963 this dome has been an intersection point for triangulations by NGS. Its position can be found as NGS PID = HS4867 where it is designated ``North Dome''. [NGS Data Sheet]
Coude Auxiliary Telescope coelostat
The coelostat for the CAT is situated in a structure just below the south end of the Shane coude room.
New Crocker Dome
The dome is marked in black on the 7.5' USGS topo map. This implies that it must have existed by 1955. The only instrument which anyone can recall in this dome was a 5- or 6-inch camera borrowed from Pasadena in the 1950s. For most of its history this dome has lain empty. During the 1980s and 1990s it was used by Gene Harlan for some of his personal telecopes.
wooden pad and pier atop Tycho Brahe Peak
There is a wooden platform with a steel pier just east of the Crocker Dome. It sits on the high point of Tycho Brahe Peak, which was levelled slightly to accommodate it. This was constructed by Gene Harlan for use in seeing monitoring experiments (1960s? 1980s?), and it had a canvas dome. Steve Vogt and friends may also have used this pier while students at Berkeley.
Cinder Block polar pier just northeast of New Crocker dome
This structure held several fixed telescopes aimed at Polaris for seeing monitoring experiments that were performed by Gene Harlan. (1960s? 1980s?)
Tauchmann Dome
The Tauchmann dome is located atop the new water tank on Huyghens Peak (just above the ruin of the Old Crocker Dome). It is marked in black on the 7.5' USGS topo map, but that dot may well be the underlying water tank. The blueprints for the dome are dated 1950, and the dome can be seen in a painting dated 1955 that is currently hanging in the dining hall.
Laboratory and Measuring Building
Around 1956 the Meridian Circle and Fauth Transit sites were obliterated by the construction of a new office wing east of the 12-inch refractor dome at the north end of the Main Building. This structure remains to this day and houses the current Mt. Hamilton Post Office.
Library and Office wing of the Main Building
Some time between 1955 and 1961 another new wing was added to the main building. It adjoined just south of the central vestibule and proceeded to the east. Its contents were presumably removed to UC Santa Cruz when the observatory headquarters was moved there in the late 1960s. Checkin dates on many volumes of the Lick library indicate that they were received in 1969. During the seismic renovation of 1988 this wing was deemed to be compromising the integrity of the Main Building, and it was demolished.
24-inch/KAIT Dome
This structure does not appear on the 1955 version of the USGS 7.5' Lick Observatory quadrangle, but it does appear on the detailed 1961 engineering survey. The dome is between the 1882 water tank and the 150000 gallon tank, and the 261000 gallon tank sits east of the dome. See entry for the Purple Dot.
150000 gallon water tank on Kepler Peak
This structure was built before 1955 for it is visible on the USGS 7.5' Lick Observatory quadrangle. See entry for the Purple Dot.
261000 gallon water tank on Kepler Peak
This structure was built in 1964. It sits between the 1882 tank and the 150000 gallon tank, and it is east of the 24-inch/KAIT dome. See entry for the Purple Dot.
Purple Dot on Kepler Peak in USGS 7.5 minute topographic quadrangle
No structure which corresponds to this purple dot has ever existed, and the topography could not support one. This would be unremarkable except that there is a published location for a dome at its coordinates.

The original epoch of the USGS 7.5' Lick Observatory topographic quadrangle was based on aerial photographs taken in 1953 and field checking done in 1954-1955. At this time the structures on Kepler Peak were the 1882 brick and cement tank to the north and the 150000 gallon steel tank to the south. The purple layer of USGS photo revision is based on aerial photographs taken in 1968 and not field checked. By this time both the 24-inch Dome and the 264000 gallon (1964) steel water tank had been added. Both new structures lie between the older structures, and from aerial photographs alone it is impossible to determine what is what. The photorevisor was apparently confused by the tight array of circular structures and added a circular dot north of the two original dots.

When James Van Nuland measured the topo to determine positions he was informed that the purple dot was the 24-inch dome, and in 1984 this position was published in the Astronomical Almanac.

12.5-inch equatorial pier/CCD Comet Camera Outhouse
The structure near the Shane containing the pier of the amateur 12.5-inch equatorial upon which was mounted the CCD Comet Camera.
The Rev. Laurentine Hamilton Monument Cuppola
This structure was built when the back yard of the main building was renovated in 1992?. From a distance it strongly resembles a dome, but it is not. Its position and size closely match that of the dome of the 6.5-inch portable refractor which existed very early in Lick history.

Steve Allen <sla@ucolick.org>