The link below is to a pdf that contains a table giving daily details of the total of 38,946 deaths in March 1918 listed by the Commonwealth War Graves Commission website.  The relatively quiet first twenty days of that month included deaths of three Orcadian sailors and three soldiers.  When the Germans launched the Kaiserschlacht ("Kaiser's Battle") on the 21st, the over 8,000 British soldiers killed that day included 11 Orcadians.  17 more Orcadian soldiers died in desperate fighting that month, as British Fifth Army and the right wing of Third Army were driven back across the 1916 Somme battlefield.  Face photos of 13 of the soldiers are shown in the pdf, with brief detail of all 34 deaths.  Their full photos and biographies of the Newlands Brothers of Harray and John Osborne of Burray are available in the RBLS Memorials website, where the death of Duncan Webster is also covered in the story of Herbert Mackenzie of South Ronaldsay.  The biographies of the four South Ronaldsay men killed in March 1918 are included in George Esson's book "For Freedom & Honour", available in local bookshops.