Summary from Wikipedia

During the early 19th century, French culture experienced a period of 'Egyptomania', brought on by Napoleon's discoveries in Egypt during his campaign there (1798–1801), which also brought to light the trilingual Rosetta Stone. Scholars debated the age of Egyptian civilization and the function and nature of the hieroglyphic script, which language if any it recorded, and the degree to which the signs were phonetic (representing speech sounds) or ideographic (recording semantic concepts directly). Many thought that the script was used only for sacred and ritual functions, and that as such it w ...