μεγάλα ὠφελήσεσθε πρὸς ἱστορίαν τῶν κοινῶν → that will be of great benefit to you in order to understand public affairs
aggĕrātĭo: (adg-), ōnis, f. 1. aggero,
I a heaping up; in concr., that which is heaped up, a mole, dike (not before the Aug. per.): naves supra adgerationem, quae fuerat sub aquā, sederunt, Vitr. 10, 22, 263; Just. 2, 1 fin.>