Latin both is and was used to spread information and knowledge. Look at scientific nomenclature, classic Catholic texts, or the art of the Renaissance; Latin is usually the basis of, lr at least or included in the work itself. Latin was used for this purpose because, as Latin is a dead language, it doesn’t change. Any other language, as it is still spoken, may be morphed or changed with small inconsistencies in dialects or spellings over time. Since Latin isn’t regularly spoken, it allows for knowledge to remain the same over time and lands. This is why Latin was the choice for a universal language used to communicate the vast amounts of know,edge being discovered at the time.
The severed snake represents the colonies if they do not work together. He used this to explain to colonists that the only way to defeat the British was to stand together with everyone together like the parts of the snake.