BACK ROAD ADVENTURE

You'll Find Bird's-eye Views and an Old Observatory Atop Harquahala Peak

Harquahala Peak loomed just over the next hill, Lor maybe just around the next hairpin curve, where the deeply incised road seemed to vanish against a jumble of sedimentary rocks.

Cheryl Blanchard knew our route exactly, but this peak near Wickenburg involved terrain new to me. Blanchard, an archaeologist with the Bureau of Land Management, agreed to guide me to an unusual ruin on the summit.

Most of the ruins in Arizona are remnants of prehistoric Indian communities or the skeletal remains of desiccated mining towns. Not so the ruin at Harquahala. This recent relic of scientific exploration is called the Harquahala Peak Smithsonian Observatory.

From photos, I knew this structure with the lofty title was a tin-clad building similar to sheds I'd sometimes found at abandoned railroad sidings. It didn't look like any observatory I'd ever seen. The structure's story intrigued me more than the building itself, and, frankly, a chance to spend a day in that barren No Man's Land around Harquahala Peak seemed even more appealing.

We left Wickenburg on a chilly morning and drove west on U.S. Route 60 to Aguila. At Aguila, we turned left (or south) onto the paved Eagle Eye Road and drove 18.5 miles to our turnoff .5 of a mile past Milepost 9. The Harquahala Mountain Road sign, which recommends a four-wheeldrive vehicle, is on the left side Of the road. It points across the highway to the unpaved road that winds 10.5 miles up to Harquahala Peak. We turned right. The road looked smooth at first, but before long it became the sort of terrain where even javelinas must have second thoughts. In some sections, it became so rocky and rutted that we tossed like a couple of stones inside a lapidary tumbler. Four-wheel drive shouldn't be recommended for this trek - it should be required. Blanchard dropped into fourwheel drive, and we proceed ed at a walking pace. In that isolated landscape, temptation to get sidetracked emerged everywhere: A narrow wash disappearing into a puzzle of boulders where the Earth had convulsed eons ago looked inviting; lichen-coated limestone and chunks of rose quartz begged for closer examination; the muted colors of every plant and rock, deepened by the mixture of rain and snow that had preceded my visit by a day or two, could have lured me off the track for hours. When the desert blooms in the spring, the saguaro forest intermixed with ocotillos, ironwoods, chollas, paloverdes, mesquites and creosotes dominates the views on both sides of the road. Inch by inch, we made our way to the 5,681-foot summit of Harquahala Peak, where the road ended. Harquahala lies in the upper Sonoran Desert, a water-scarce place where many plants don't grow much taller than an average human being. In summer, temperatures exceed 100 degrees; the thought of snow would challenge the imagination. But this was winter and the strange scene before us had prickly pear cactuses, ocotillos and jojoba bushes standing in an ankle-deep carpet of snow. Harquahala is an anglicized translation of a Mohave Indian expression, Aha qua hala, which means "water there is, high up," probably a reference to a spring (now dry) about a mile below the summit. The tallest vegetation consisted of very old ironwoods, saguaros, and a scattering of arthritic mesquites. Treacherous veins of Christmas cactuses were barely visible between the tiny leaves of the creosote bushes and the hair-thin tines of the ubiquitous chollas.

A small group of scientists had settled on this remote summit in 1920 to conduct an esoteric experiment in longrange weather forecasting. "How do people find such places and what do they do there?" I wondered.

In this case, Blanchard said, the nature of the Smithsonian's project determined the location to be used. Samuel Pierpont Langley established what is known today as the Smithsonian Astrophysical Observatory in 1890. Langley was an inventor, among other things. His main invention was a device called the bolometer, which detected heat emitted from any warm object as infrared radiation. When Langley aimed this instrument at the sun, he was able to map the entire infrared spectrum known at the time, but then he stumbled onto something new. As he later wrote, "[I] found, suddenly and unexpectedly, a new [part of the infrared] spectrum of great extent, wholly unknown to science."

Langley's research led him to believe that further study of what he called "the solar constant," the amount of heat reaching the Earth from the sun, might vastly improve the science of weather prediction. Langley's premise, still debated in scientific journals, got its first test on Mount Whitney in California. Later a permanent facility for long-range observing

was established at Mount Wilson near Los Angeles, which proved imperfect because of its proximity to the smoke and dust of the city. There weren't enough clear days for collect-ing data.

Charles G. Abbot, a Langley protege and pioneer in solar research, was dispatched to find other locations for observatories in places with low humidity and clear skies. The weather bureau office in Phoenix voted for Harquahala Peak, some 70 miles northwest of the city and roughly midway between Wickenburg and Quartzsite.

Abbot went to see the spot and was impressed, he said, because “the prevalence of dwarfed vegetation in the desert and upon Mount Harqua Hala [the spelling in use at that time] would tend to keep down dust,” a factor that would contribute to the accuracy of the data collected.

The observatory's original adobe structure, which later was clad with sheet metal to protect it from the winds that tear across Harquahala Peak much of the year, is all that remains on the mountaintop the Smithsonian used from 1920 to 1925. The observatory remains a memorial to American science and provides a good excuse for exploring and climbing to the top of an isolated peak in the Sonoran Desert.

TIPS FOR TRAVELERS

Travel Advisory: The observatory is off-limits and located behind a barbed-wire fence, but visitors may sign the summit book located in front of the historic site and read the experiences of fellow Harquahala adventurers.

Warning: Observe all signs warning of high voltage danger. Do not attempt to reach the summit or remain atop the mountain during thunderstorms, which can quickly become dangerous. Back road travel can be hazardous if you are not prepared for the unexpected. Whether traveling in the desert or in the high country, be aware of weather and road conditions, and make sure you and your vehicle are in top shape. Carry plenty of water. Don't travel alone, and let someone at home know where you are going and when you plan to return. Odometer readings may vary by vehicle. Additional Information: Bureau of Land Management, (623) 580-5500.