The Journal of San Diego History
SAN DIEGO HISTORICAL SOCIETY QUARTERLY
Winter 1989, Volume 35, Number 1
Thomas L. Scharf, Editor
by Maria Eugenia B. De Novelo
Milton Fintzelberg Second Place Award
San Diego History Center 1988 Institute of History
Santa Rosalia, Baja California, had its beginnings when a rancher named Jose Rosas discovered curious round green pellets in its vicinity in 1868. Interested in their possible value, he sent them to Guaymas to be analyzed via the captain of a ship he traded with, and the response was quick. Two Germans, G. Blumhardt and Julio Müller, paid Rosas 16 pesos to reveal the site and began prospecting immediately.1
After two years many other parties had declared claims, yet Guillermo Eisenmann and Eustaquio Valle managed to merge most of the concessions granted to other small companies which had been working the area since 1870.
Further interest was sparked in 1883 when gold was discovered in Las Palomas, creating a gold rush centered around Calmallí. Due to this, in 1884 a commission was sent by the Mexican government to explore Baja California’s mineral resources. This commission carried out extensive studies and determined that from 1870 to 1884, 42,000 tons of copper had been mined and, up to July of 1884, 6,000 ounces of gold had been produced.2
By that year Eisenmann and Valle were operating a copper mining company called El Boleo (after the Spanish word for the copper-bearing pellets). The enterprise entailed eleven mines with a good network of tunnels and galleries located at mining camps called Santa Rosalía, Providencia, Purgatorio and Soledad.3
One hundred Yaqui Indians brought from the prison of Guaymas were the first laborers to dig the mineral, and ore was brought out of the mines in leather sacks called “tanates.” Many more Yaquis would be brought in time to live in barracks and continued to be an important labor force.4
Since 1872 copper had begun to be exported to Europe, mainly to Swansea, England.5 Due to this, and undoubtedly also to the gold rush, interest arose in Europe to find out more about the location, and in 1883 two Frenchmen arrived to reconnoitre the terrain. One was Professor M. Fuchs of the School of Mining in Paris, and the other, M. Cumenge, was an honorary engineer of the Mining Corps.6
They calculated that 700,000 tons of copper of 12% fineness existed in the ground, with a duration of 50 years’ exploitation. Due to this study, the House of Rothschild-which then monopolized the world market of industrial minerals-bought from Eisenmann and Valle their concessions, and on May 16, 1885, formed in Paris the Compagnie du Boleo, with a capital of 12,000,000 francs financed by the Bank of Mirabeau.
The Díaz government wished to dissipate the influence of too much capital investment in Mexico by the United States, and had eyed Europe as a place to divert its international commerical relations. Even though there was still some resentment due to the French invasion of Mexico in 1864, times had changed sufficiently to permit negotiations with France.
The company was to be exempt from all customs duties and import and export tariffs on fuel until 1942. Employees were also exempt from military or civil service. Moreover, the original concession consisted of square miles, plus 46 square miles for pasture to the south of the mines. As time went by, other extensions were added until the land involved a maximum of 2,317 square miles.7
The company directed all business from its offices in the Rue de Provence, Paris; Sansome st., San Francisco; in Santa Rosalía and later, in Tacoma, Washington. The directors and the main executives were always French, although in time, once the Mexican personnel had been trained, many of them had the opportunity to participate in higher ranking jobs.
So it was that at 27°25′ north latitude and 112°20′ west longitude, overlooking the magnificent Sea of Cortez, a rectangle of three by five miles was chosen for their mining concession, between the sea and a geological fault that constitutes a vast plain of “an astounding regularity, lightly tipped toward the sea and marked by great perpendicular canyons 100 to 400 yards wide, running toward the coast.”8 The lodes to be developed confirmed their grandiose and wrenching names of Providence, Purgatory, Solitude and Hell.
By 1886 the French had begun building their main center of operations in the canyon of Providencia, calling the town Santa Rosalía, after the arroyo than ran through there and the Mission of Mulegé.
On the other side of the gulf, 98 miles away, was the port of Guaymas with a population of 15,800,9 and of importance because the railroad that came from Laredo, Texas, ended there, while to the south another line linked it to Mazatlán and Manzanillo. In Baja California the nearest towns were San Ignacio to the north and Mulegé to the south, but these did not amount to 1000 inhabitants combined. Clearly, Guaymas was and continued to be the important base for the development of Santa Rosalía.
All of a sudden the land explored by the Jesuits in the 18th Century, abandoned by its native inhabitants due to the death toll they suffered from contagious diseases contracted from other races and from the impact of another culture, was put in upheaval by the new interest that united it with Europe.
The first Director was fittingly M. Cumenge, who in 1883 had explored the property and set down estimates that were the basis for the company. With him came his countrymen from France, who worked on the Boleo’s objectives with discipline and energy. Ships arrived continually from Europe carrying rails, engines, railway cars, other sorts of vehicles, and an electric plant. From Canada and Oregon, numerous shipments of lumber were unloaded.
Narrow streets were laid out, and to their sides the tress of North America became small houses for miners and other employees. Visible from the gulf, to the north and on a higher level, was Mesa Francia, where the directors of the company lived. To the south lay the Mexican Ravine where the Mexican employees and miners settled, and where the customs and internal revenue offices were located. Along the coast, between Mesa Francia and the port, they built the electric plant, railroad yard, workshops, and storage buildings for machinery.10
The town was divided into four distinct parts: Santa Rosalía with eleven streets and four avenues, Providencia, Purgatorio and Soledad, each with a school, store and mining installations.
By 1886 the first furnace was working, while around it an impressive infrastructure was being consolidated.11 Water was brought from Arroyo Santa Agueda, 22 miles to the south, by six-inch pipes, and wells were dug to provide for the different townships.
In time, two breakwaters made of slag blocks weighing up to half a ton each were built to form a port. When it was finished in 1922, it had an area of 40 acres of safe water, with three docks where up to six ships could moor.12
When the Yaqui Indians were no longer sufficient to work the mines, the classic system of the Díaz era was followed. Employees were recruited through advertising in the papers of Mazatlán, Guaymas and Topolobampo. The contractors were paid two pesos for each man employed, and they were sent form those ports to Santa Rosalía in the steamships Korrigan II, Carlos Pacheco and Curazao. The contractors offered advantageous terms but delivered harsh realities.
Life in Santa Rosalía was far from agreeable, and rebellion among the miners occured soon enough. They complained of the terrible, unsafe conditions. Allowance of water per family came to a bucket a day and they had to pay for it. In the Mazatlan paper Correo de la Tarde, an open letter appeared May 19, 1899 denouncing the ill treatment received and advising those wanting to migrate to the mines not to do so.13
Soon enough the company began to add more water to the daily ration. This, plus medical services were to be free. Due to the lack of Mexican laborers willing to migrate to Santa Rosalía, in 1903 the company contracted for 2,000 Japanese. Of the first 500 who came, only 50 stayed. The rest left, protesting the danger of the constant gas explosions in the mines. Neverthless, soon after, 432 other Japanese did manage to stay. In that same year 3,000 Chinese joined the labor force.14
Few towns have known such abrupt demographic highs and lows as Santa Rosalia. In 1887 it had around 4,000 inhabitants; in 1900, 8,269, of which approximately 200 were French. In 1905 the population had dwindled to 6,568. Cholera, yellow fever, tuberculosis and typhoid caused a population crisis from 1901 to 1903, a period in which 1,209 deaths occurred in three years. This sad statistic gives an idea of the poor health conditions that prevailed. However, toward 1910 the population had risen to 10,172. Of these, 4,100 were working at El Boleo.15
Because of the epidemics, French doctors were brought in 1903, and by 1905 there were four doctors, a nursing station, a male nurse, a woman nurse and two pharmacists. In that same decade a hospital with 18 beds was built, and doctors of other nationalities began to arrive.16 Since there was no sewer system, a tank wagon went by daily to collect the deposits from each house, the cargo was carried and deposited out of town. When for some reason the collection failed, the stench was unbearable. Twenty years had elapsed and still what little water they had, had to be taken in buckets to the houses.
The climate, with temperatures from 56° to 62° F. from October to April, and 80° to 92° F. from May to September, with barely .04 inch of rain per year, added to the stress of life and labor. Smoke from the chimneys descended on the town, causing the eyes to itch, and stuck to the throat with a sweetish taste.
From 1890 to 1899 El Boleo was the leading producer of copper in Mexico. Later, even though it was extremely important, it took second place to the mines in Cananea, Sonora.
The depth of the mines varied between 160 and 515 feet with a total of 78 miles of galleries in 1906. All excavations were hand-made and the cost of removing the ore was one franc per ton.17
By 1896, 56,199 tons of copper had been produced.18 By 1905, extraction had soared to 261,000 tons. In 1907 there was a crisis when copper prices fell, but by 1910 production reached over 366,000 tons. Both 1910 and 1913 were all-time peak years, with 13,000 tons of pure copper being produced in each. Gross earnings in 1912 came to 380,000 pounds sterling. From 1900 to 1912 the company enjoyed profits of 25 to 200% a year.20
To realize this enormous production all the mines were connected to the smelter by rail. Ore was loaded onto the cars, and these were emptied at the smelter, where ten furances of 150 tons capacity each had been working since 1901 and were replaced by others of larger capacity in 1906. The smelter had four big Connersville blowers driven by two 175 horsepower engines.21 Water for the water jackets was distilled form the sea and pumped from subterranean cisterns at a rate of 10,000 gallons per minute by a 250 hp engine. Slag, when cooled, was emptied by electric locomotives into the sea, discoloring it black. The ultimate processing produced “blister copper” ingots of 20 × 2 × 6 inches, which were exported to Falmouth, England, in the beginning, and later to the United States to be refined by the electrolytic process.22
The generators were driven by four steam engines, and all the electric power came from the central plant at Santa Rosalía. 23 In addition to the industrial electricity, the plant provided current for 1,500 light bulbs and 65 arc lamps.24 After Mexico City, Santa Rosalía was the second city in Mexico to have electricity.
Don Arturo Meza, who worked as chief electrician for the company until it closed, testified to the excellent electric installations which the company ran with a maximum of reliability and quality.
At first a great part of all edibles came from Sonora or the United States and even France. But soon other sources were developed. When the land concession was augmented to 2,317 square miles, much of it was allocated to agriculture. It is widely acknowledged that under the direction of Ernest Michot the company had great drive.25
One of Santa Rosalía’s landmarks today is the little church of Santa Barbara. About 1896, a group of ladies asked Mrs. LaForgue to intercede with her husband, the Director of the company, to build Catholic church. He agreed, but as he was leaving for Europe the matter was postponed. But in Brussels, in 1897, he came upon a church designed by Gustave Eiffel for Africa, made of metal, because wood was devoured by the white ants of that continent. For some reason it had not reached its first destination, and when LaForgue saw it he bought it and shipped it to Santa Rosalía.
The first baptism in the new church was celebrated on January 2, 1898, by Father Juan Rossi, an Italian priest who had come from the West Indies, where the House of Rothschild also had interests. So, from their antipodes, an Italian priest and a Belgian church met in a remote Mexican mining town run by a French company.26
If in some ways there were cordial relations between the company and the settlers, in other there was certainly a good deal of tension between the miners and the directors. Wages were low and men were charged fines for such transgression as not reporting to collect their pay on time, for talking about their bosses, or for occupying barracks without permission. Moreover, in the beginning, they were charged for the oil that they consumed in the mines to light their way.
In 1905, a hundred men rebelled and demanded their passage back to Mazatlán. The company convinced 50 to return to work, dispatched 47 to Guaymas and sent the three leaders to jail at Mulegé.27
This tug-of-war continued throughout the years with many ups and downs, and gained momentum after the Mexican Revolution of 1910-1917 ended. Since Santa Rosalía was so closely linked with Guaymas, it was inevitable that repercussions of that conflict should spill over across the gulf. Pancho Villa’s men twice took the port and in 1914 were even welcomed with an orchestra at the breakwater. But by 1917 Venustiano Carranza had become President of Mexico, a new order was being imposed, and all concessions to foreigners were put under scrutiny. The company alleged it was losing money due to the drop in copper prices, and wanted to reduce salaries.28 This was not allowed by the government, but neither were they raised, as the miners had demanded. However, the government did begin to apply tariffs on the copper exported by the Boleo Company.
The Revolution also affected the demographic situtation. In 1918 Santa Rosalía had 11,660 inhabitants, of which 3,228 worked at El Boleo; but in 1919 only 5,916 were left-1539 of whom worked for the company. This dramatic decrease was due to a migration en masse to the area around Mexicali, where cotton fields had been opened to settlers by Colonel Esteban Cantú, Governor of the Northern Territory of Baja California.29
It is important to note that the school system in Santa Rosalía had progressed from the original four school houses. In 1917, 1,273 children attended classes and a large school had been built which today stands as the City Hall. A high school did not exist until 1940. Before that, students had to go to the mainland to further their education.30 Nevertheless, it is surprising to see how the people of Santa Rosalía, some with only a grammar school education, grew up with an ability to express themselves fluently and correctly, both orally and in writing.
From its beginnings Santa Rosalía depended on the sea. The ships which brought coke for fuel returned to Europe loaded with lumber from Oregon, wheat from Washington and guano from South America. In addition to this foreign traffic, the company operated its own fleet, which through the years consisted of Korrigan I, II, III and IV. For port service there were a dredge, five tower cranes, eight iron boats, four lumber boats and three canoes.
The company also employed the American steamship Jim Butler, and the Providencia. In 1917 it acquired the Argyll (later renamed San Luciano), which carried fuel oil for the smelter when coke was not longer brought from Germany. The trip to San Francisco took around six days. Each ten days there was a ship bound for Europe.31
Two ships are remembered today with special interest: the Selene, an English ship which ran aground and could not be repaired, and which later became a storage house, and the Korrigan IV, which had the peculiarity of navigating to one side.32
Feelings must have run high when arriving travelers entering port saw the silhouette of the Hotel Central on Mesa Francia. This building, as were all residential buildings for the directors, was made of lumber, of broad inverted “V” ceilings, simple and functional with a roofed porch shading rectangular windows all around. From there, the viewer could look down on the modest rows of wood houses on the lower levels, and the port. Far from France and the refined things its name entails, Santa Rosalía must have seemed like a banishment.
To preserve decorum the company demanded that its directors wear black tail coats to all formal occasions, and to preserve high spirits, three dances were organized each year: New Year’s, Carnival Saturday, and Bastille Day (July 14).
Although it was the manifest policy of the company that its employees not marry Mexicans, love triumphed time and again.
People of Baja California were cordial, and immigrants from Sonora and Sinaloa were good humored and expansive, so Santa Rosalía became a dynamic and versatile place. Its people loved music, formed their own orchestras, and even took them to picnics or to the port to welcome ships and seem them off.
Santa Rosalía was a place of clashing contrasts and situations. It had a scarred backdrop of copper hills, a black-tinted shore, French silks, fine perfumes, crystal, Bordeaux wines and Duret cooking oil, sharing the scene with flour tortillas, giant lobsters, abalone and chimney dust.
To be in Santa Rosalía was something. They had a theatre where they showed French movies, but over at Soledad, they even said and “hello” to a passing burro, because other than that nothing passed until pay day-once a month-when they made tamales and the men got drunk.
Yet, the town became involved in world affairs. By 1914 international fleets from Germany, the United States, Japan and Canada had come into the gulf-supposedly to aid their citizens in case they were affected by the Revolution, but in reality to reconnoitre the area due to the tense world situation caused by the coming of World War I.34
In spite of all of their precautions, a dozen German sailing ships were trapped off Mulegé and Santa Rosalía when the war broke out in August 1914. For years they bobbed lazily at anchor with their disheartened crews, who lived through it all thanks to the help of Germans of Guaymas who had been nationalized as Mexicans. When the war ended some of their crews remained in Mexico, others went to the United States, and the rest returned to Germany. It was not until 1921, more than two years after the war ended, that the ships were expropirated and sold to different shipping firms.35
The 1920’s were marked by labor struggles usually voiced through the labor union’s weekly papers; the 1930’s by the installation of cable buckets done by German engineers in 1935-1936. These buckets carried minerals for 11 miles in a straight line from San Luciano to Ranchería and, after working hours, they also carried people back and forth. It was the first funicular system ever installed in Latin America.36
Professor Fuchs had said the mineral would last 50 years and time proved him right. By 1938 the Boleo Company had turned over most of the mines to small groups called “poquiteros,” while it remained in charge of the smelter.
The company was making moves to close down when World War II broke out. Copper was urgently needed by the Allies and production was speeded up. The union promised not to strike and in return each miner received 1.25 pesos daily as a bonus.37 When the war ended copper prices fell, and in 1945 400 miners were laid off. As if this were not enough, another hurricane hit in 1946, just as hard as the one in 1931.38
Production had decreased to 4% at the beginning of the 1950’s. It was inefficient, as some of the installations were more than 60 years old. The company compensated the remaining workers, gave away the old wood houses, and on February 1, 1954, El Boleo was shut down.39 Pedro Mahieux was the French Director who closed the company-which some remember with acrimony but many more with equanimity for, apart from the conflicts which labor and capital inevitably face, there was a warmth of rich human relations between friends, sweethearts, coworkers, and families.
After the French left, the population decreased to 4,000. People thought the town would die, but it didn’t happen. The union fought to keep the mines going, rented the smelter from its owners, and many families that had emigrated returned. Still the going waa hard; Japan and Germany bought the copper, but prices were low.
In the 1960’s the Compañía Minera de Santa Rosalia, which the Mexican laborers formed after the French left, was producing barely 2,147 tons a year.40 Soon the copper was gone and it was decided to process ore from Chile and Peru. Then the weekly paper, El Independiente, denounced the new company for not distributing profits properly.
Life had not been easy for Santa Rosalia; lack of communications with the rest of the peninsula had held it apart. To travel to Ensenada or La Paz took two whole days in either direction when going overland. Air travel was sporadic and did not begin on a weekly schedule until the 1960’s.
In 1972 the new Transpeninsular Highway was built throught the town, giving it new life. By the end of the decade Santa Rosalía had 15,000 in habitants, the ferry to Guaymas was running regularly, and there were canneries which processed fish. But the smelter was counting its final days.
The federal government stopped all subsidies in April 1986, and all the smelter workers and the remaining administrative employees were dismissed.
Clearly, Santa Rosalía, due to the combined influence of the French, Sonora and Sinaloa, was a town different from all others in Baja California. Modestly structured, built for hard work and hard work only, it managed to raise itself above its principal purpose to become a complete little city which, with all its simplicity, still celebrated carnivals, elected a queen every year, organized balls, formed jazz orchestras, and overcame one storm after another.
Today, the copper that initially gave life to Santa Rosalía is scattered throughout the world. The House of Rothschild may have drained its mountains but in the town there is a persistent entity that refused to die.
Here and there in some homes one can find reproductions of Monet, Degas, Pissarro or Seurat … nostalgic reminders of a bygone era. Portions of the smelter have slowly disappeared, as if by magic. The cable buckets mysteriously went, and so did the railroad cars and even the rails. Every day something more was missing.
Before the last remaining locomotive should disappear, it was rescued and placed in the middle of a small park, facing the sea, where today it stands as a monument to a unique and fascinating past.
The Paul Garnier clock on the smelter, which began to tell time in 1907, has stopped; no one knows when. But time inexorably goes on, and Santa Rosalía, with its black port, its scarred hills, phantom smelter and static locomotive no. 7, is in itself a monument to a colonial saga and to the spirit through which it lives on.
1. Ramón Cota Meza, Centenario de Santa Rosalia, 1985. pp. 8, 11.
2. Joaquín M. Ramos, Report on works performed by the Exploration Commission of Baja California done in 1884, Presented to the Secretariat of Development, 1886, p. 9.
3. Ibid., p. 126.
4. Ibid., p. 128.
5. Ibid., p. 128.
6. León Diguet, Territorio de la Baja California. París-México, 1912. p. 28.
7. The Copper Handbook*, p. 388.
8. Edmund Fuchs, Bulletin de la Societé Géologique de France, XIV (1885-1886> París, p. 79.
9. Juan Manuel Romero Gil, Población y Fuerza de Trabajo en el Mineral de Santa Rosalia, “El Boleo” 1885-1920. El Colegio de Sonora, Oct. 1985. p. 7.
10. Ibid., pp. 29, 30.
11. Leon Diguet Territorio, p. 28.
12. M. Peyrot G, Un viaje a Baja California. Editorial Litorales. México, D.F. 1968, p. 232. The Official Mining Directory of Mexico, Vol X. states that in 1908, 125,000 tons of merchandise were handled on the docks and 7,250,000 feet of lumber from Oregon arrived. In one year 500,000 tons of mineral were moved.
13. Juan Manuel Romero Gil Población, pp. 8,9,10.
14. Ibid., p. 22.
15. Ibid., pp. 4, 31, 32. See statistics Nos. 8, 9, and 10.
16. Leopoldo López y Luis C. Espinosa, Informe rendido sobre las condiciones en que se encuentra la Compañía “El Boleo” en Santa Rosalía, B.C., 1917. p. 3.
17. The Copper Handbook, p. 389.
18. Ramon Cota Meza, Centenario, p.22.
19. The Mexican Mining Journal*, August 1913, p. 402.
20. Juan Manuel Romero Gil, Poblacíon, p. 36.
21. The Copper Handbook, p. 389.
22. M. Peyrot, Baja California, p. 233.
23. The Copper Handbook, p. 389.
24. Directorio Oficial Minero de México.
The Copper Handbook also states that the steam engines generated 2,000 h.p. of which 1,500 were transformed by two 3-phase generators of 500 kw, and two 3-phase generators of 250 kw.
25. Ernest Michot apparently took over in 1909. I have been unable to define the year precisely. he became ill and left around 1919. In 1908 and 1909, according to Centenario de Santa Rosalía, 220 acres were opened to irrigation to the north, in San Carlos; in Santa Agueda, there were dairy barns; and in San Bruno 94 acres with olive trees, cereal crops and chickens. In San Marcos, 30 acres of sugar cane were planted, which produced 3,800 pounds of sugar loaf.
26. Francisco de Antuñano, Centenario de Santa Rosalia, p. 165.
27. Juan Manuel Romero Gil, Población, pp.13, 14, 26, 27.
28. L. López y L.C. Espinoza, Informe, pp. 4, 6, 7, 10, 11.
29. Juan Manuel Romero Gil, Poblacion, Statistic No.9.
30. L. López y L.C. Espinoza, Informe, p.4.
A.N. Teachers worked for the company until 1935, when the government federalized all education in the city.
31. L. López y L.C. Espinoza Informe, p. 4.
32. Carlos V. Rosas Osuna, Centenario de Santa Rosalía, pp. 146, 147.
Korrigan I (1890) ran aground in 1907.
Korrigan II (1898) weighed 289 tons.
Korrigan III (1912) was sold in 1939.
Korrigan IV (1938) was sold in 1965 to Ruffo Hermanos, of La Paz, Baja California.
33. Consuelo C. de Nopper, Memorias, “Razón Política, “Revista, July and August, 1986. Santa Rosalía.
A.N. Señora Consuelo C. de Nopper was married to Auguste Nopper, who directed the compnay for 35 years, circa 1919-1954. It is important to note that although organization was meticulous, labor was risky, both at the mines and at the smelter. The former, as all mines, were also somber. The “William Shaft” had a depth of 760 feet, and was divided in two levels. Its tower rose 65 feet and the iron cages were operated by electricity. In these cages, men, work materials and animals went up and down. The pumps installed to drain water were insufficient; the mines were suffocating during summer, and miners worked with water up to their waists. It is vividly recalled by Mrs. Nopper that the mules threw themselves on the ground and kicked joyfully when they came out of the shaft.
34. Roberto Gastelum Arce, Centenario de Santa Rosalía, Santa Rosalía, 1985, p. 124. Gastelum states there were two German warships, the Nuremburg and Leipzig; four U.S. destroyers and the cruisers California and Albany; one Japanese ship, the Idzimo; and one Canadian, the Allgerine.
35. Harold D. Huycker., Jr., To Santa Rosalía Further and Back, Newport News, Virginia, 1970. p. 378.
36. Carlos V. Rosas O., Centenario, p. 106.
37. Consuelo C. de Nopper, Memorias, p. 10.
38. M. Peyrot G., Baja California, p. 235.
M. Peyrot reports another hurricane hit in 1959. The port was not repaired until 1965-1966.
39. Ascención de Dios Carbajal, Centenario de Santa Rosalia., p.131.
40. M. Peyrot, Baja California, p. 236.
41. Fedrico Campbell, Zeta, Tijuana, B.C., December 19, 1986.
Baja California al Día 1924. Aurelio de Vivanco.
Campell, Federico, Zeta, semanario. December 19, 1986. Tijuana, B.C.
Centenario de Santa Rosalia, Roberto Gastelum Arce, Edición del Gobierno de Baja California Sur 1885-1985.
The Copper Handbook, 1908 Boleo. Horace J. Stevens, (Houghton, Michigan: published by author). Volume VIII (1908).
Diguet, León, La República Mexicana. Teritorio de la Baja California. Reseña geográfica y estadistica.
El Directorio Oficial Minero de Mexico, Vol. X., 1908, México, D.F.
Documentos del Mineral de Santa Rosalía, Gobierno del Distrito Sur de Baja California, La Paz, Sección I. Nos. 2649, 2591, 336.
Fuchs, M.E., Bulletin de la Societé Gélogique de France, Vol. XIV 1885-1886. Paris.
Huycke Jr., Harold D., To Santa Rosalía Further and Back, Newport News, Virginia, 1970.
Informe hecho por los Ingenieros Leopoldo López y Luis C. Espinoza sobre las condiciones en que se encuentra la compañia de El Boleo. Baja California. Inventario e indice de las misceláneas de la Bibliotecas Publica del Estado de Jalisco. Miscelánea #792, Entrada no. 11.
The Mexican Mining Journal, July and August, 1913. Mexico City. Periódico bilingue.
Nopper, Consuelo C. de, “Razón Política. “Nos. 45 and 47, 1986.
Peyrot, G.M., Un Viaje a Baja California, Editorial Litorals, México, D.F., 1968.
Ramos Joaquin M., Ingeniero de Minas. Informe respecto a los trabajos ejecutados por la Comisión exploradora de la Baja California el año de 1884 — presentado a la Sría. de Fomento, 1886.
Romero Gil, Juan Manuel, Población y Fuerza de Trabajo en el Mineral de El Boleo 1886-1920. Colegio de Sonora, Oct. 1985.
Saladin, Edouard, Bulletin de la Societé de Lindustrie Minérale, Mines de Cuivre du Boleo. Vol VI (1892), Saint-Etienne, France.
Transactions and Periodicals. The Boleo Copper Mines. Mexico. Federated Institution of Mining Engineers, London, V. (1892-1893).
A. N. Special thanks go to Mr. Carlos V. Rosas for placing his extensive and invaluable archive at my disposal, to Professor Don Chaput, of the Natural History Museum of Los Angeles, for sharing many important documents regarding El Boleo, and to Mr. Philip M. Klauber for editing this article in English.
THE PHOTOGRAPHS are courtesy of the author.