Letter of introduction for Dwight B. Heard on the arrival of National Park Service Director Stephen T. Mather to Phoenix. Mather's visit includes trips to Roosevelt Dam and Tumacácori.

Letter from Carl Hayden to Arno B. Cammerer on behalf of Jesse L. Boyce's complaint. Hayden states that Boyce believes Crosby's report to be inaccurate and an underestimation of the danger of the stored explosives.

Letter from Jesse L. Boyce to Jack in which he refers to W. W. Crosby as a "damn carpetbagger" and his frustration at Crosby making him out to be a "liar."

Letter from Jesse L. Boyce to Carl Hayden stating there is 30 tons of dynamite located in the Grand Canyon near tourist sites.

Letter to Jesse L. Boyce from unknown author (possibly Jack) about the investigation into the powder magazine located in the Grand Canyon. Some personal news is included in the letter such as the writer's marriage to the daughter of C.A. Taylor, former Supervisor of Cochise County.

Letter from Jesse L. Boyce to Carl Hayden stating that the Director of the National Park Service will order Colonel Crosby to remove the dynamite from the park.

Letter from Jesse L. Boyce to Jack regarding the storage of dynamite in Shoski Canyon.

Letter from Carl Hayden to R.P Gilliland regarding the sale of Bright Angel Trail (Ariz.) and construction of the President's Highway from Maine, AZ to the Grand Canyon.