The construction of dry stack walls (that is, wall construction without the use of mortar), has been a feature of human development for thousands of years. Extraordinary examples of dry stack stonework can be seen at Chaco Canyon in New Mexico; cliff dwellings in Arizona and Colorado; Mayan architecture in Mexico and Central America; and at the Inca city of Machu Picchu in Peru – to name only a few. These examples show that prehistoric cultures recognized the importance of durable construction and, at least in the case of Machu Picchu, the Incas developed techniques that were capable of surviving earthquakes. The walls at Machu Picchu are undoubtedly the finest dry stack construction ever devised.
Figure 1: Dry Stack and Mill Walls
The history of dry stack walls in our neck of the desert may not be as ancient, durable or glamorous as the sites mentioned, but the region still provides a rich testament to this type of construction dating from the latter half of the nineteenth century. These examples owe their use to mining, pioneer settlement and the development of transportation in Territorial Arizona. Their construction was for utilitarian purposes and achieved their desired results while maintaining a conscious focus on economy.
The purpose of this five part series is to describe, through photo and text, a historical context for the type of dry stack construction you are likely to encounter in the mountainous mining areas. Whether you are a fellow historical researcher or simply enjoy recreational trekking, your ability to locate and identify dry stack structures will increase your “situational awareness” about mines and settlements.
Quality and durability of dry stack walls varied greatly during the pioneer and prospecting era. Once you begin studying these structures it becomes relatively easy to distinguish the “Do it yourself” method from well-engineered and patiently constructed walls. For example, an itinerant mine worker might only have been interested in blocking wind and rain with a temporary shelter, where a mine owner needed a durable road that would not wash out during seasonally heavy rainstorms. A dry stack terrace wall at a mine had to be well-engineered to support tons of shipping ore and the constant vibrations of a stamp mill, while the construction of a foundation wall for a house or cabin did not require the same standards. It probably came down to the individual’s sense of permanency and the resources at their disposal. For a ‘jack’ who may have earned $3.00 per day in the tunnels and shafts of a hard rock mine, there was little incentive to make an investment in a permanent structure.
Similarly, primitive pack trails that crossed the rugged mountainsides might be only two feet wide and did not require the scale or precision of wall construction demanded by wider roads that were needed to support heavy loads of equipment and ore shipments.
If you were a miner with several tons of mill ready ore (but no mill), or if you needed equipment and supplies, then you would understand why good roads and trails were vital. The railroad did not reach Wickenburg until 1877. Even then, transportation between a railroad town and the remote mining sites and settlements depended upon horses and mules. That helps explain why arrastres (the poor man’s mill) were heavily used in the remote mining areas and – more than likely – explains the absence of milling operations even at many large mine sites. Milling equipment was simply too bulky or heavy to transport over these “rough and heavy” roads.
So, with this introduction, let’s study a few of the dry stacks that you will find in the vicinity of the Wickenburg/Weaver/Bradshaw mountain ranges (east and north) and the Harquahala Mountains to the west.
Stage Coach and Freight Roads
When you are exploring remote areas you will be presented with many opportunities to spot historical features, such as the dry stack wall shown below. Notice that the actual ‘road’ is virtually impossible to detect because trees and shrubs now cover the route.
Figure 2: Stage Coach Road
The dry stack wall shown in Figure 2 is part of a stage coach road east of Wickenburg, situated between Hamlin Wash and Morgan Butte, south of Buckhorn Road. This road runs in an easterly direction for several miles and then branches in three directions (north, east and south). It connects to several historically important mine sites and settlements. The view in this photo looks in a westerly direction. This road probably pre-dates modern Constellation and Buckhorn Roads by two or three decades. Unless you are particularly observant, you are unlikely to see this feature, since there is only one viewpoint that exposes the old road. It illustrates several points:
- The original surface and slope of an old road or trail will inevitably be altered by decades of runoff and sedimentation that settles onto the abandoned roadway.
- Natural growth of vegetation will eventually reclaim the original margins of the roadway.
- A dry stack wall – regardless of its size – may be the only way to locate an old road.
Figure 3: Stage Coach Road Close-up View
The view in Figure 3 is a closer examination of the dry stack wall. This photo angle is only possible by hiking from above (right) to this south-facing slope, or via foot, horse or ATV from below (left). It is a particularly impressive dry stack wall; measuring nearly 100 feet in length and approximately twenty feet high at the center.
The builders of this wall are unknown to me but, based upon legend, were probably Chinese laborers. A notable feature of the wall is that it had a ‘staggered’ construction. In other words, the upper portion of the wall was offset from the lower portion. This allowed the upper wall segment to rest upon the reinforced foundation below it and contributes to overall structural integrity. Close examination of the wall reveals that many of the rocks were shaped to provide a tight fit. Also, the individual rocks do not protrude from the contour – the exposed surface of the wall is generally smooth.
Within a few hundred yards of this location there are another half-dozen dry stacks. Where there are no walls to support the roadway, sedimentation from the uphill slopes has virtually erased any evidence of the road, and native vegetation has obscured what remains of the original roadway. These dry stack walls have survived the elements for nearly 140 years and remain in wonderful condition to this day.
If you think of mine roads as branches from a stage coach route (that is, ‘highways’ leading to arterial roads and trails), then you can find many trails that will take you to old mines. Figure 4 shows a dry stack wall that was part of the famous “$17,000 Road constructed by George Mahoney between the settlement of Constellation and O’Brien Gulch. One of the dry stacks is visible to the left and right of the Saguaro cactus in the photo center. Mahoney discovered the Gold Bar Mine in 1877, but was constrained from transporting supplies and heavy equipment by the lack of an adequate road. He undertook the construction of this road in 1884 to address the problem.
Figure 4: Mahoney’s Road
To the left and right of the Saguaro cactus you can see a dry stack wall that is considerably more modest in construction than what is shown in Figure 2. In contrast to the previous wall, this dry stack made use of more ‘irregular’ shaped rocks. In other words, the rocks were not shaped by stone masons to provide a tight geometrical fit. Instead, the placement of individual rocks in the wall was based upon their individual shape. Mahoney’s road was narrower and less well engineered, but it served its purpose very well. I have never attempted to count the number of dry stacks on the route between Constellation and the bottom of O’Brien Gulch but I estimate there are at least a dozen walls along this route. The road is now nearly 130 years old. Today it can only be traveled by foot for the entire length, but the walls remain a testament to its durability.
Other stage coach and freight road walls have not survived the test of time, as seen in Figure 5. In this example, the ravages of weather have claimed the center portion of the wall. In spite of its collapse from seasonal flooding, it still serves as a marker to pioneer activity so, in that regard, its condition doesn’t really matter.
Figure 5: Collapsed Dry Stack Wall
What do these photos suggest to you? To me, I see careful, well engineered construction. The rocks were carefully stacked and, when necessary, were shaped by stone masons to provide the best possible fit in the wall. Even though the dry stack in Figure 5 has partially collapsed, it is only the result of heavy runoff on a road that has been abandoned for at least a century. Figure 4 suggests, to me, a more economical approach to construction. It did not require shaped stonework but it is still well built. The hillside roads shown in Figures 2, 3 and 5 were also generally wider than Mahoney’s Road into O’Brien Gulch.
It is important to consider that these roads were not ‘public’ highways in the sense that we are accustomed today. They were all built at the expense of a mine owner or stage/freight company for the purpose of expediting supplies, equipment and passengers. They were, in effect, only as wide and sturdy as needed to accommodate the type of traffic of the era and to endure (without excessive maintenance) for as long as possible.
The next article (Part Two) will deal with mine trail construction and will illustrate a different type of trail structure and dry stack walls. Examination of these trails and walls will show that they were typically more economical and designed with more modest objectives than what you have seen in Part One.
Last 5 posts by Allan Hall
- Wickenburg Hospitality Comes in Many Forms - December 15th, 2010
- Calliandra Eriophylla is Native to the Wickenburg Area - December 9th, 2010
- Goodbye, Old Bridge - November 29th, 2010
- Abandoned Mines Part III: Preserving the "Whispering Ranch" Mine - March 25th, 2010
- Abandoned Mines Part II: Protective Closures - March 10th, 2010