In 1830, the quarry located near Philadelphia, from a depth of 21 meters was removed a large block of marble. Sawing plate, the workers drew attention to the rectangular notches, a width of about 13.8 cm and height 1.6 cm, which strangely resembled the embossed letters.
It is curious that scholars of the nineteenth century came to the conclusion that the origin of the letters difficult to explain by natural causes and natural physical processes. It has been suggested that the letters – the product of reasonable people, lived in very ancient times.
About this amazing discovery, wrote in 1831 American journal of American Journal of Science.