One of the great advances that occurred in Western mining in the 19th century was the aerial tramway.
Although at times used in the logging industry, aerial trams quickly became popular as a means to transport ore from the mine to the mill in a fast, efficient and economic manner over rugged, mountainous and oftentimes inaccessible terrain.
Aerial tramways evolved from the European introduction of wire rope in the 1830s, which replaced hemp rope previously used on ships. Wire rope had the benefit of being lighter and stronger. As the century progressed, wire rope was used in the manufacture of cables to transport freight and materials both in Europe and the United States.
English inventors Andrew S. Hallidie and Charles Hodgson and American inventor Charles Huson pioneered the development of aerial tramways in the Western states. Hodgson was responsible for building the first aerial tramway in the West for the mines at Treasure Hill, Nev., in 1870-71.
Over the next 50 years, several hundred tramways were built across the West for the purpose of transporting ore. Many of them were a single-rope tramway design composed of grooved pulleys and towers supporting a single-line device that received a wire spliced together to form a continuous loop. This design was limited, covering a maximum of four miles with a load capacity of less than 200 pounds.
By the turn of the century a double-rope (or bi-cable) design was perfected by German engineers Theodore Otto and Adolph Bleichert. This new design, known as the Bleichert system, was more durable, allowing for a greater carrying capacity of up to 2,000 pounds per car.
From the 1890s into the 1990s more than two dozen aerial tramways operated in Arizona at sites including the Magma Mine at Superior, the Mammoth Mine near Oracle, Virginia Chief Mine in the Dos Cabezas Mountains, the Christmas Mine in the Dripping Springs Mountains in Gila County and the Old Dominion Copper Mine at Globe.
Two aerial tramways operated at the Grand Canyon during the 1950s, including one at the high-grade-uranium Orphan Mine on the South Rim and the other operated by the U.S. Guano Co. to extract bat guano from a natural cavern at the western part of the canyon.
During the 1920s, the use of aerial tramways for mining began to decline. The reasons for this were advances in mining methods, including open-pit mining, and technology, including trucks, shovels and conveyor systems that allowed for road improvement, increasing the accessibility of the mines.
One example is one of the last tramways built in Arizona, at Morenci, in 1970. It connected a limestone quarry east of the San Francisco River with the Phelps Dodge smelter at Morenci. The cars were capable of hauling 2,000 pounds of limestone. Within a decade, the aerial tramway was closed after a better limestone deposit was discovered elsewhere. Phelps Dodge dynamited the tramway in 1997.
Although aerial tramways will probably never regain the significance in the mining industry they had 100 years ago, some will continue to be built and operated, depending on topography and economics.
"Mining Tales" writer William Ascarza is writing a book about the history of mining in Arizona, and he's looking for historical and modern-day photographs depicting mining operations, towns and camps to include in the book. If you'd like your photos included, email him at firstname.lastname@example.org
William Ascarza is an archivist, historian and author. Email him at email@example.com Sources: "History of Mining in Arizona, Vol. III" by Michael Canty, Michael Green and H. Mason Coggin, 1999; "Railroads of Arizona, Vol. III: Clifton, Morenci and Metcalf, Rails and Copper Mines" by David F. Myrick, 1980; "Riding the High Wire: Aerial Mine Tramways in the West" by Robert A. Trennert, 2001.