Bernard J. S. Cahill
American architect and cartographer
Bernard Joseph Stanislaus Cahill (London, January 30, 1866 – Alameda County, October 4, 1944) was an American cartographer and architect who invented the octahedral "Butterfly Map" (published in 1909 and patented in 1913). An early proponent of the San Francisco Civic Center, he also designed hotels, factories and mausoleums like the Columbarium of San Francisco.
His polyhedral Butterfly World Map, like Buckminster Fuller's later Dymaxion map of 1943 and 1954, enabled all continents to be uninterrupted, and with reasonable fidelity to a globe. Cahill demonstrated this principle by also inventing a rubber-ball globe which could be flattened under a pane of glass in the "butterfly" form, then return to its ball shape.
A variant was developed by Gene Keyes in 1975, the Cahill–Keyes projection.
See also
World map
Waterman butterfly projection
Octants projection
Cahill–Keyes projection
References
Selected works
"An Account of a New Land Map of the World" (The Scottish Geographical Magazine, 1909–09) pp. 449–469 [reproduced in 21 jpegs] The first publication and exposition of the Butterfly Map.
"Map of the World" (U.S. patent 1,054,276, 1913) Washington, DC: United States Patent Office, 1913-02-25; filed 1912-03-05
"Geographic Globe" (US Patent 1081207[link removed], 1913: rubber-ball globe which can flatten to a Butterfly Map, or return to ball shape.)
"Projections for World Maps" (1929) —continued in separate pdf:— "A New Map for Meteorologists: Equally Suitable for Small Areas, Continents, Hemispheres or the Entire World" – both from Monthly Weather Review, 57/4, 1929–04) pp. 128–133; illus.
"One Base Map in Place of Five" (1940) Monthly Weather Review, 68/2, 1940–02, p.
“Bernard J. S. Cahill” enters the record as american architect and cartographer. Crown Archives preserves that source wording while asking what Bernard, Cahill and American can confirm, complicate or overturn.
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Biographical claims are most persuasive when dates, appointments and relationships can be traced to records created close to the events described. The source revision retrieved here is dated Jul 27, 2026. The linked authority identifier is Q4893274. VIAF identifies the subject as 240824794. The Library of Congress control number is no2014059638. 3 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1866, 1944, 1909 and 1913.
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