Correspondence regarding the clean air campaign, her husband's work towards this, causes of cancer (diesel fumes and air pollution), her own position as an author and historian not a medical professional, "Defume" speech by her husband. Attached is Lady Fergusson Hannay's letter to the Daily Telegraph "Tobacco or Diesel" (this refers to her husbands work and Percy Stock's figures on lung cancer in rural and urban areas). Pybus drafts replies regarding his own work and Sir Walter Fergusson Hannay's work and use of it in the aim for clean air (this is drafted on the back of a National Geographic Subscription). An obituary for Fergusson Hannay in "Vital Statistics" is available. Pybus' replies also suggest he is making progress with the campaign locally, he also mentions his correspondence with Vauxhall regarding an exhaust filter. A later letter from Fergusson Hannay shows Pybus sent her a paper which she suggests he should send to Gerald [Watson?] M.P. and Rupert Spier M.P. (Spier is linked to noise pollution), her husband was chair of the Noise Abatement Society. Lady Fergusson Hannay goes into detail about her husbands death, her own personal situation and experiences, including how her dog reacts to living in London.