JOHN FLANDRICK PHOTO
A.S. from Santa Ynez has a 26-inch square, canvas-mounted, blue-toned old map of a “Portion of the Rancho Santa Margarita, and adjoining lands, San Luis Obispo, CAL, property of Ferdinand Reis.” The cartographer, often a major clue to the value of old maps, is T.A. McMahon, CE, and the map is dated 1901.
Interestingly, the property is vast: The map states “Containing: inside Rancho (exclusive of R.R. Right of Way, R.R. Quarry and Town site) 14,840.63 acres” and the outside of the Rancho property at 3,432.93. Quite a surveying job in 1901, when electronic resonance instruments were a thing of the future and the topography, as it is here, is complex.
The scale, says the map, is 40 chains to an inch, a grand total of 18,273.56 acres.
A “chain” is a unit of length often used in old land maps made by the U.S. General Land Office. The antique measure is also called a Gunter’s chain or surveyor’s chain. Cartographer McMahon, a county surveyor by profession, is not one of the West’s most famous mapmakers, such as the long-serving head of the Corps of Topographical Engineers, John James Abert (1788-1863), who was followed in this family of cartographers by his son, James William (1820-1897). I find one other map attributed to McMahon, “Official Map of Contra Costa County, California.” It’s actually credited to T.A. McMahon and Wm. Minto, civil engineer, dated Feb. 4, 1885, in an interesting little catalog from 1887.
Late 19th and early 20th century maps of the West are particularly interesting because they are physical representations of the philosophy of an era, when classifications and categories defined natural phenomena, Indian tribes, rivers and ranchos. Research into period maps is difficult with minor cartographers; in the 19th century, cartographers were simply working men.
McMahon’s map of Contra Costa is mentioned in the University of California Library Bulletin No. 9, A List of Printed Maps of California (Berkeley, 1887). One of the most famous of all California cartography aficionados is mentioned as the inspiration for this ambitious book — Hubert Howe Bancroft‘s (1832-1918) History of the Northwest Coast is included as a centerpiece of the Berkeley library’s catalog. The 1887 book claims to have sent out request letters asking for maps. Pleas were sent to libraries, halls of records, railroads, real estate offices, bankers and mining company’s offices, as well as state and government bureaus. A list of maps and cartographers known in 1887 is cited.
What a stretch it is to think of the effort to gather maps together in 1887, and what a novel idea back then. Today, Google Earth and Microsoft mapping, drone shots and laser/lidar photography is ubiquitous; we forget that the early cartographer’s job was challenging and literally earth-defining, when one miscalculation could change fortunes forever.
Rancho Margarita, writes Michael A. Moodian, author of Rancho Santa Margarita, a book from the Images of America series, was one of a few ranchos that served Mission San Juan Capistrano; Southeast Orange County was interconnected by ranchos of such vast acreages. These included Rancho Santa Margarita y Las Flores, today occupied, in part, by Camp Pendleton.
Wonderful talks of the rancho must have been told as McMahon measured those 18,273.56 acres. The seal of the city of Rancho Santa Margarita bears three gold keys; this iconic imagery bears witness to an attempted theft in 1818 of three locked boxes of gold and silver from Mission San Juan Capistrano. The mission was under siege by Argentinian robbers: Priests secreted chests of treasures to the old Trabuco Adobe, where they were buried, lore has it, under a sycamore tree. At the date of this map (1901), a fire damaged the old adobe, which had been built by the mission priests in 1806 as a herd station for Trabuco Mesa. McMahon might also have heard that this same adobe housed Pio Pico in 1846 as he hid from the Americans in the Mexican-American War.
A.S. was intrigued that this old map was mounted on canvas, and although he thought the map must be rare, because of its age, I found others like his for sale for around $100 on abebooks.com and raremaps.com. Because of the skill today in the reproduction of older maps, we would need to see the material on which comparable maps are mounted to make sure of the authenticity of the maps offered for sale. Another resource, A.S., is the Bancroft Library at Stanford. Call and make a request to see a copy of your map.