1541. Acquaintance based on outer characteristics is given by their facial expressions, especially in the province of the eyes, and also by their speech, which is different from other people's speech. It is not made up of sounds, like the languages of our earth's inhabitants, but is a kind of tacit speaking, belonging to a purer atmosphere, which is aimed at [the listener's] mouth. There it enters, then passes through the Eustachian tube, which seems to be their organ of hearing. One of them spoke with me in that language, so that I would learn about it. It entered between my lips, the tissues of which were poised to receive this different kind of messages. Then it goes inside through the Eustachian tube, then upwards, and is clearly heard. It is a speech much richer and more perfect than one that strikes the ear, conveying many things at once.