Laboratory sieves were used to determine the granularity of dry earth and analyze its thickness and size, for later production of concrete.
Later the dry earth was classified. The sieves have a sifter and various openings. On the sieve there is the following inscription: “Mecánica científica, Inmaculada Concepción, 24 Madrid tel. 2697089. Serie ASTM, Número 200, Abertura 0,074”.