Engineering Designer, Louisville Water Company, Louisville, KY, 1909; Architectural Superintendent/Engineering Designer, Fred R. Dorn, Architect, Los Angeles, CA, 1912-1913; Architectural Superintendent, Haenke and McDonald, Architects, Los Angeles, CA, 1913; Partner, Watson and Dubbs, Architects and Engineers, Los Angeles, CA, 1913-1914; Partner, Pierre Davis, Walter Davis and Loyall F. Watson, Architects, Los Angeles, CA, 1914-1915; 1st Lieutenant, United States Army, Corps of Engineers, Second Training Regiment, Camp Humphries, VA, 1918; his World War I draft registration form indicated that Watson was an "Architect and Engineer." In 1918, he had an office in Room 330 of the Union Oil Building, in Downtown Los Angeles, CA. Partner, [David J.] Witmer and Watson, Architects, Los Angeles, CA, 1920-1945. Partner, Witmer, Watson and [Lowell Walter] Pidgeon, Architects, Los Angeles, CA, c. 1948-1958; in 1948, the firm was located at 816 West 5th Street in Downtown Los Angeles. Under Loyall F. Watson, the American Architects Directory of 1956 indicated that the firm of Witmer, Watson and Pidgeon had formed in 1950; this was not correct, as this firm's name appeared in the Los Angeles telephone book of 1948.

Member, American Institute of Architects (AIA), Southern CA Chapter.

Secondary school education at the Army and Navy Preparatory School, Washington, DC; B.S., Civil Engineering, Rensselaer Polytechnic Institute, Troy, NY, 09/1903-1907.

Born in Brooklyn, NY, Loyall was a Navy brat, although it doe not appear that he followed his father to posts around the US. According to the US Census of 1900, Rear Admiral Watson indicated that he resided in San Francisco, CA; presumably, that was where his wife and son remained while he sailed through the Suez Canal aboard the U.S.S. Baltimore that year. He attended the prep school in Washington, DC, and he listed Louisville, as his place of permanent residence in 1907, the year he graduated from college. By 1910, now on his own, Loyall resided in the Radisson Hotel in Minneapolis, MN, presumably working in the city as a civil engineer. He moved to Southern CA by the late 1910s. The US Census of 1920 indicated that Loyall and his new bride lived at 2621 Juliet Street in Los Angeles. In 1940, Loyall, his second wife, Mildred, and Richard lived at 532 Gramercy Place in Los Angeles, as lodgers in the house of Mary Elizabeth Peek (born 10/13/1859 in RI-d. 08/29/1950 in Los Angeles), an 80-year-old woman living with her grand-niece, Joyce Abbott (born c. 1917 in NJ) and a maid, Dolly Wilson (born c 1899 in LA). What the Watsons' connection to her is unknown. Loyall Watson passed away in San Bernardino County, CA.

Loyall had been born at the Brooklyn Naval Yard Hospital in 1885. His father was John Crittenden Watson (1842-1923), a career US Navy officer who rose to the rank of Rear Admiral and served until 1904. As a Flag Lieutenant, John C. Watson served with then Rear Admiral David Farragut (1801-1870) on the Union steam sloop Hartford during the Civil War's Battle of Mobile Bay; this was the battle in which Farragut made his famous quote, "Damn the torpedoes, full speed ahead." David Farragut and his wife Virginia Dorcas Loyall Farragut (1824-1884) had a son, Loyall Farragut (1844-1916) whose first name honored his mother's surname. It was for David Farragut's son, that Loyall Farragut Watson was named. His mother was Elizabeth “Lizzie” Thornton (1850-1922), whose father had come from GA and mother from AL. John C. Watson's parents also had come from the South, (although he stayed loyal to the Union during the Civil War), his father having come from KY, his mother from AL. Loyall Watson listed his father as his next of kin on his 09/12/1918 World War I draft registration form. At that time, John C. Watson lived on Wyoming Avenue NW in Washington, DC. John C. and Elizabeth Thornton Watson were buried at Arlington National Cemetery.

Loyall F. Watson married twice; he first wed Florence Leigh Watson (born c. 1889 in AR) on 03/30/1919 in Little Rock, AR. (Her parents were Southerners like Loyall's; her father had come from GA, her mother, AL.) Their marriage lasted nearly 11 years, her death coming prematurely on 03/20/1930 in Los Angeles. She was interred in her hometown of Little Rock, AR. (Florence's mother also died young.) His second marriage occurred in 06/22/1938 to Mildred Mary Angle (b. 04/26/1894 in WI-d. 02/09/1979 in Los Angeles County). He and Mildred were laid to rest at Arlington National Cemetery, where his parents were buried.

Loyall and Florence had one son, Richard Leigh Watson (born 03/20/1923-died 07/05/1999).

His 1907 yearbook at Rensselaer Polytechnic summarized the youthful Loyall Watson: "Oh, ye shades of the American Navy, here is truly one of your greatest sons! Behold his serious and thoughtful brow. Of what is he thinking? Ah, we may not answer that with certainty. But we may conjecture. He may be having a day dream of his future successes, for this man plans to earn no less that $100,000 a year before he gets through, and he does not expect to go on the vaudeville stage either. What tobacco does he smoke? Ah, he never uses it. Such thoughts come quite natural to him. Or, again, he may be thinking of more fields to conquer among the fair sex. This is, indeed, his greatest weakness. Yes, a new one every week or so and each affair is so serious, that one often fears he may despairingly end his life. In this man we also have a great student. He loves the quiet seclusion of his rooms at night, but if we steal, expecting to find him at his books, we may be disappointed, for it is more than likely he is writing to Frances or some other way down in Kentucky." (See the Rensselaer Polytechnic Institute Yearbook, 1907, p. 74.) In 1918, his local draft board representative listed Watson as being of medium height and thin build, with blue eyes and brown hair. Watson returned to Los Angeles from Honolulu, HI, between 01/12/1929-01/18/1929 aboard the S.S. City of Los Angeles. By about 1940, Watson had developed a significant hearing problem. According to the American Architects Directory of 1956, Watson had traveled to England, France, Spain, Italy, Germany, Austria, Holland, and Belgium. Watson served as the Clerk of Session for the 1st Presbyterian Church of Los Angeles in 1929-1930. He volunteered as an Elder at the Wilshire Presbyterian Church from c. 1934-1960; his connections at this congregation enabled him to obtain a commission to alter the church's choir in 1935. Vice President, Ellis-Orpheus Club of Los Angeles, a non-profit, charitable, group with branches throughout Southern CA, 1951-1952; President, Ellis-Orpheus Club of Los Angeles, 1953-1955.