Uti harena primum purissima asperrimaque paretur, caementum de silice frangatur ne gravius quam librarium, calx quam vehementissima mortario mixta, ita ut quinque partes harenae ad duos respondeant.
First let the purest and roughest sand be provided; then rubble is to be made of broken flint, no piece weighing more than a pound; the strongest lime is to be mixed in a trough, five parts of sand to two of lime.
final_alignments\Vitruvius_Architecture_Book_8.json