These documents, which cover the period January-December 1921, consist of letters from Mina Miller Edison to her youngest son, Theodore. They were written during the second semester of Theodore's sophomore year at the Massachusetts Institute of Technology (MIT) and the first semester of his junior year. Theodore also spent most of the summer of 1921 in Cambridge, and almost a third of the letters date from that period. The notation "Save" in Theodore's handwriting appears on most of the envelopes. Some envelopes bear the notation "N.S. Scrap" suggesting that Theodore may have intended to destroy the letters.

About half of the letters were written during the winter of 1921. One of the main themes in these letters is Mina's concern about the human consequences of the downsizing at Thomas A. Edison, Inc., particularly its effect on her son Charles. Included are comments about the dismissal of several MIT fraternity brothers whom Charles had brought into the company—John P. Constable, who had been serving as chief engineer of the West Orange laboratory since 1918; John Hamilton Scott, who was fired for copying one of Edison's questionnaires, and Wirt Russell Robinson. "Papa has practically dismissed all the men that Charles got or were with him," she remarks in one letter. ". . . Papa does not realize how deep a hurt he has made. I wish I knew how to show him. My heart aches for Charlsie."

Mina's concern about the impact of the layoffs on the esprit de corps of the entire organization is evident in the letters. "What can we do to have father dear see that he is crushing all the spirit throughout the plant?" she laments in early January. "Everybody is thoroughly unsettled and Papa does not seem to grasp it at all." The letters also reveal Mina's frustration at her husband's inability to understand her point of view, which she attributes in part to his deafness. "He will not see my point," she complains in one letter, "but thinks I talk foolishness." On the other hand, she dismisses reports that "Papa is a little unbalanced or loosing out in his mental capacity," attributing such rumors to disgruntlement on the part of the "discharged men."

Even apart from the downsizing, Mina's interest in the management of Thomas Edison's businesses is well documented in the correspondence from this period. Among the topics discussed in the letters are her brother John V. Miller's aspirations to succeed Richard W. Kellow as Edison's personal secretary; Mina's suspicion and dislike of Financial Executive Stephen B. Mambert; Edison's efforts to sell the property of the long defunct New Jersey & Pennsylvania Concentrating Works; the sale of the Bates Manufacturing Co. to Charles's friend and former assistant, Clarence S. A. Williams; difficulties with the masters at the disc record plant, which Mina attributes to "that miserable Moore" [Edison's chief assistant Sherwood T. (Sam) Moore]; the hiring of Amos H. Curry, president and general manager of the Texas-Oklahoma Phonograph Co., to take over the management of the Musical Phonograph Division from William Maxwell.; and the hiring of a music scout [possibly Godfrey Taylor] to visit the dance halls and identify dance songs popular with young people. There are also occasional comments about general business conditions, which Mina characterizes as "picking up a little" in a letter from April 29 but as "dark" in a letter from July 6.

Eight letters from July and August contain a detailed and sometimes humorous account of the two-week camping trip in the mountains of Maryland and West Virginia undertaken by Thomas and Mina Edison, Henry and Clara Ford, Harvey and Idabelle Firestone, and a retinue of maids, valets, newspapermen, and Secret Service men assigned to guard President Warren G. Harding, who also briefly participated. Mina's dislike of the whole proceedings, which she characterizes in one letter as a "circus" and in another as an "advertizing trip" for Ford