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The ancient Romans discovered a mineral on the slopes of Mount Vesuvius. The mineral when mixed with limestone and burned, produced cement, that hardened under water as well as in the air. 1_______. As time passed, the new material not only became the preferred type for use in all their buildings projects but changed the character of Roman construction. Masonry of stone or brick was used to construct only the surfaces of masonry piers and walls but the interiors were filled with large amounts of the new type of mortar.
We now know that mortar continued the main ingredient of modern Portland cement. 2_______. With the fall of the Roman Empire, knowledge of concrete construction was lost. 3_______. In 1824 an artificial cement, named Portland cement, was patented. 4_______.
This cement was harder and stronger than the ordinary lime mortar they had been using
Thus, one can say that the Romans were the inventors of concrete constructions
But in the eighteenth century English inventors began experimenting with both natural and artificially produced cements
This type of cement soon became very popular and the name Portland is in common use in the present day