This past Sunday, I had the pleasure of interviewing Bob Manning, whose father, Jim Manning, "owned" the Puerto Rico mine from 1929 to his death in 1940. He had a partner, Earl C. Johnston, that continued the operation until after WWII. I put owned in parenthesis because in that situation in Mexico, you "denounce" the land, which gives you many of the rights of ownership, without actually owning the land, or something like that. I'm still researching the specifics of denouncement.
According to the history books, the tramway was built to transport ore from the Puerto Rico mine to the US.
Bob was eight in 1929 and remembers riding the ore buckets from the small tramway that transported the ore from the mouth of the Puerto Rico mine down the mountain. It was dangerous, especially when the buckets were full of ore, so his dad constantly yelled at him and his brothers whenever they did it. According to J.A. Gregory's master's thesis on the Puerto Rico mine in 1908, the "gravity cable" was 1900 feet long. This wasn't the aerial tramway to the cable terminal in the US. It was simply the way they got ore out of the mine for transportation.
Gregory also describes the two roads to the mine. One was used when traveling to/from Boquillas and the other was used to haul the ore to Quatro Cienegas. Bob remembers wagons drawn by 10 mules that hauled the ore to Quatro Cienegas. They were double wagons, with the first wagon full of supplies for the trip and the second one full of ore. His dad would only let him ride for four miles before he had to walk back, so he never made it to Quatro Cienegas.
Bob spent his summers at the mine, as his dad worked there from 1929 until just a few days before his death in 1940. His dad rarely came back to the US.
Interestingly enough, Bob had never heard of the aerial tramway and cable terminal. When I showed him the USGS map that clearly showed the tramway, he asked me, "Are you sure this isn't a proposed tramway?" I said it was the tramway that started operations in 1910.
I recorded him as he read J. A. Gregory's master's thesis and he recognized much of what Gregory described. In it, Gregory describes the aerial tramway; the fact that it was recently surveyed and towers were currently being built; and that the embarkation terminal was five miles away from the Puerto Rico mine. Gregory calculates the cost of transporting the ore from the mine to the tramway using mule drawn freighters and makes a suggestion for installing a narrow guage railroad.
As I said, this was the first time Bob had ever heard of the tramway and he's the closest thing to a living eyewitness I have, even though he was eight years old the first time he went to the mine in 1929 and that was 10 years after the tramway was abandoned. He asked me a question that I don't have answer to, namely, "Why did they need this aerial tramway when they had wagon roads?"
It's a good question. I assume the answer is that when you factor the cost of the construction of the tramway, the cost of transportation over the tramway and on to Marathon, the cost of transporting the ore over to the US side is less expensive than transporting it through Mexico.
Now I assume that's true. I don't know for sure if that's true. Gregory only does a financial analysis assuming the tramway is operation. He doesn't do a comparison analysis by shipping to Quatro Cienegas via wagon train.
Still, it's a good question.
Another good question is why the tramway ended five miles away from the Puerto Rico mine? Why didn't they just go the extra distance to the most productive mine in Boquillas? Could it be this was the most convenient collection point for all the mines in Boquillas? Or, did they simply run out of money and that's as far into Mexico as they afford to build?