Sir William John Thompson Slides A collection of glass lantern slides belonging to Sir William John Thompson, the majority created [for him] by Thomas Holmes Mason. The slides are statistical in nature, dealing with Irish censuses, birth and marriage rates, and diseases frequency and mortality rates. The slides were probably produced to illustrate talks given by Thompson, either as Registrar General for Ireland or to the Statistical and Social Inquiry Society of Ireland. Thompson presented a number of papers to this society, between 1911 and 1926, on the Irish Censuses and on mortality rates in Ireland. [1910s-1920s]