TEPANTILTLA MURAL

The murals of the Classic era site of Teotihuacan are filled with speech scrolls, in particular the tableaus found within the Tepantitla compound—this mural, for example, shows no fewer than 20 speech scrolls. In Mesoamerica, the speech-scroll is usually oriented with the longest outer edge upward, so that the central element (or "tongue") curves downward as it spirals. Some Mesoamerican speech scrolls are divided lengthwise with each side a different shade

Speech scroll, also called a banderole or phylactery, is an illustrative device denoting speech, song or other types of sound. Developed independently on two continents, the device was in use by artists within Mesoamerican cultures from as early as 650 BC until after the Spanish conquest in the 16th century, as well as by European painters during the Medieval and Renaissance periods.

From:
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Image: Photo of a section of a mural from the Tepantitla
compound in the Mesoamerican ruins of Teotihuacan.