Both Florence and Edith offered their services to the British Red Cross at the War Office in London, to provide a radiological service to support the troops in Europe, on the day Britain declared war. Their offer was refused, because they were women. Florence set up her own unit with the Women's Imperial Service League and spent the next 6 months in Europe. Edith organised supplies from London where she also served on the League's committee. Florence returned to London at the time Edith resigned from the London School of Medicine for Women. Edith contacted the Scottish Women's Hospitals (SWH), an organisation formed in 1914 to give medical support in the field of battle and financed by the women's suffrage movement. The organisation had gained agreement to set up a new 250-bed tented hospital at Domaine de Chanteloup, Sainte-Savine, near Troyes (France), funded by the Cambridge women's colleges of Girton and Newnham and it became Edith's role to plan and operate the x-ray facilities. She established stereoscopy to localise bullets and shrapnel and introduced the use of x-rays in the diagnosis of gas gangrene, interstitial gas being a mandate for immediate amputation to give any chance of survival.