A family tree of the provinces and colleges of the Jesuit order, with horological markings to show the time in each location relative to noon in Rome. Engraving after A. Kircher, 1646.

The diagram shows at what hour in Rome each Jesuit college elsewhere in the world is getting up or going to bed, saying mass, reading, dining, supping, etc. It was devised by Kircher, who also devised a clock of a similar kind in the form of a cross, fourteen palms high, kept in his museum (Kircher, loc.. cit.). The tree is an olive tree. Its trunk grows out of the figure of Saint Ignatius Loyola. At the top of the tree is the double-headed eagle containing a dart, labelled "Austri acus", in honour of the Austrian house and its support for the Jesuit order. In the sky above is a dove holding an olive branch, labelled "Pacem te poscimus omnes" (We all ask you for peace)