The Thornton Chase Papers are the most thorough source of information about Thornton Chase, as well as one of the most detailed sources of information about the American Bahá'í community. Filling eleven archival boxes, the papers feature carbon copies of the typed letters that Thornton Chase sent to others, plus Chase's incoming correspondence. In addition, Thornton Chase kept typed copies of every tablet of `Abdu'l-Bahá that he could locate, and he included translation information on the copies whenever he could; thus the Thornton Chase Papers are an invaluable resource for dating `Abdu'l-Bahá's correspondence (usually the Persian originals are undated). Thornton also kept typed copies of talks by Isabella Brittingham, Mírzá Asadu'lláh, Mírzá Abu'l-Fal, and himself, providing an opportunity to study the thought of these individuals.
The Thornton Chase Papers are not complete. The first round of destruction of items was conducted by his wife soon after his death. In a letter to Helen Goodall, a San Francisco Bahá'í, Eleanor noted that
It has taken all my strength to go through these papers--Fifteen hundred letters, I have burned--personal letters--
Dear Thornton, never gave up anything, in way of letters, clippings, visions, diaries, etc--
Apparently Eleanor Chase destroyed the diaries, thereby eliminated a primary source for reconstructing Thornton's life and spiritual development.
Within a month of Thornton's death, John Bosch arrived in Los Angeles to pick up Thornton's Bahá'í correspondence and papers, for Thornton had named Bosch his literary executor. Bosch and Eleanor Chase packed up the remaining papers, and he took them to his home in Geyserville, California. Eventually the papers were sent to the National Bahá'í Archives, probably after the death of John and Louise Bosch in the mid-1940s. The second round of destruction of the Thornton Chase Papers was conducted by the Bosches, and was described by Louise Bosch in a letter to Mrs. Carl Scheffler:
Mr. Chase's letters to the people, if nothing else, would constitute his memorial. He kept a copy of every letter he ever wrote. He also kept every scrap of paper he ever received. These letters filled boxes and boxes. Many of these letters we have destroyed by reason of the private nature of their contents. That is to say, my husband and I destroyed them.
Then also all of Assad'ullah's and of Fareed's correspondence with Mr. Chase we have destroyed. We have kept only letters of spiritual import.
The destruction of the letters by Asadu'lláh and Fareed was carried out because both men rebelled against the Bahá'í Faith a year after Chase's death. However, destroying the letters has only made a study of their personalities more difficult, and thus makes it harder to understand why they acted as they did. Apparently the Bosches destroyed many other letters Chase received; the papers contain only sixty-eight letters he received, but 488 letters that he sent, and usually he wrote in reply to a letter sent to him. No letters to Chase from Isabella Brittingham, Arthur Agnew, Carl Scheffler, or Willard Hatch exist, even though Thornton wrote them often, and usually he refers to a letter he had just received. Probably the Bosches decided that the incoming correspondence was not "spiritual" enough and destroyed it. Isabella Brittingham's letters, which often spoke about the troubles in the New York Bahá'í community (judging from Chase's replies to her), are a particularly lamentable loss.
The destruction of much of the Thornton Chase Papers is particularly unfortunate because some of the letters that survive bear signs of Thornton's editing of them for posterity. For example, the third page of P. M. Blake to Thornton Chase, 7 March 1900, is missing, and the fourth page has a note later added in Thornton's hand that explains it was about "a small proposed loan from the Co. Thornton." A letter from `Abdu'l-Karím-i-ihrání, dated 19 April 1901, mentions that a tablet by `Abdu'l-Bahá had been sent to Thornton Chase a week earlier; Thornton later wrote on the letter "it never was received." In 1905 he wrote a letter to suggest revisions to an author who submitted some works to the Bahai Publishing Society; Thornton later wrote on the letter "this offended." These editings are clear indications that Thornton Chase intentionally preserved his correspondence for posterity. Yet in spite of the destruction, a substantial Thornton Chase legacy remains.
Louise Bosch to Mrs. Scheffler (copy), 11 June 1935, author's personal papers.
P. M. Blake to Thornton Chase, 7 March 1900, 4, TC; `Abdu'l-Karím-i-ihrání to Thornton Chase, 19 April 1901, TC; Thornton Chase to Mrs. Louise Waite (copy), 22 October 1905, 4, TC.