They had correct views of the structure of the solar system, and knew the order of the emplacement of the planets.

They constructed sundials, clepsydras, astrolabes, gnomons.
Not without interest do we still look on specimens of their method of printing.

Upon a revolving roller they engraved, in cuneiform letters, their records, and, running this over plastic clay formed into blocks, produced ineffaceable proofs.

From their tile-libraries we are still to reap a literary and historical harvest.

They were not without some knowledge of optics.