This document is much too little known. Britain has much for which to thank Leo XIII: the red hat given to Newman, the solemn definition of the nullity of Anglican orders, St Bede’s elevation to Doctor of the Church but it is seldom remembered that almost the first act of Leo’s pontificate was the restoration of the Scottish hierarchy. This measure had been delayed for many years after the restoration of the English hierarchy because of the much greater hostility of the Protestants north of the border. It is interesting the importance Leo gives to the unflinching preservation of the Church’s doctrine concerning the unlimited material inerrancy of Sacred Scripture as “the starting-point for a return to unity“. Leo’s obvious belief in the sincerity of Scottish Protestants’ reverence for scripture causes him to lay out with unusual frankness the logical connection of such reverence to the acceptance of the infallible magisterium of the Church.