<P> The museum was concerned about heavy bombing in London towards the end of the First World War in 1917, and the Rosetta Stone was moved to safety, along with other portable objects of value . The stone spent the next two years 15 m (50 ft) below ground level in a station of the Postal Tube Railway at Mount Pleasant near Holborn . Other than during wartime, the Rosetta Stone has left the British Museum only once: for one month in October 1972, to be displayed alongside Champollion's Lettre at the Louvre in Paris on the 150th anniversary of the letter's publication . Even when the Rosetta Stone was undergoing conservation measures in 1999, the work was done in the gallery so that it could remain visible to the public . </P> <P> Prior to the discovery of the Rosetta Stone and its eventual decipherment, the ancient Egyptian language and script had not been understood since shortly before the fall of the Roman Empire . The usage of the hieroglyphic script had become increasingly specialised even in the later Pharaonic period; by the 4th century CE, few Egyptians were capable of reading them . Monumental use of hieroglyphs ceased after the closing of all non-Christian temples in 391 by Roman Emperor Theodosius I; the last known inscription is dated to 24 August 394, found at Philae and known as the Graffito of Esmet - Akhom . </P> <P> Hieroglyphs retained their pictorial appearance, and classical authors emphasised this aspect, in sharp contrast to the Greek and Roman alphabets . In the 5th century, the priest Horapollo wrote Hieroglyphica, an explanation of almost 200 glyphs . His work was believed to be authoritative, yet it was misleading in many ways, and this and other works were a lasting impediment to the understanding of Egyptian writing . Later attempts at decipherment were made by Arab historians in medieval Egypt during the 9th and 10th centuries . Dhul - Nun al - Misri and Ibn Wahshiyya were the first historians to study hieroglyphs, by comparing them to the contemporary Coptic language used by Coptic priests in their time . The study of hieroglyphs continued with fruitless attempts at decipherment by European scholars, notably Johannes Goropius Becanus in the 16th century, Athanasius Kircher in the 17th, and Georg Zoëga in the 18th . The discovery of the Rosetta Stone in 1799 provided critical missing information, gradually revealed by a succession of scholars, that eventually allowed Jean - François Champollion to solve the puzzle that Kircher had called the riddle of the Sphinx . </P> <P> The Greek text on the Rosetta Stone provided the starting point . Ancient Greek was widely known to scholars, but they were not familiar with details of its use in the Hellenistic period as a government language in Ptolemaic Egypt; large - scale discoveries of Greek papyri were a long way in the future . Thus, the earliest translations of the Greek text of the stone show the translators still struggling with the historical context and with administrative and religious jargon . Stephen Weston verbally presented an English translation of the Greek text at a Society of Antiquaries meeting in April 1802 . </P>

What did it say on the rosetta stone