kaban (kemono friends and 2 more) drawn by vostok_(vostok061)

The length of a man's outspread arms is equal to his height.

The Parthenon in Athens.

The cross-section of a jet engine. This diagram is taken Wikimedia.

Vitruvius, the architect, says in his work on architecture that the measurements of the human body are distributed by Nature as follows that is that 4 fingers make 1 palm, and 4 palms make 1 foot, 6 palms make 1 cubit; 4 cubits make a man's height. And 4 cubits make one pace and 24 palms make a man, and these measures he used in his buildings. If you open your legs so much as to decrease your height 1/14 and spread and raise your arms till your middle fingers touch the level of the top of your head you must know that the center of the outspread limbs will be in the navel and the space between the legs will be an equilateral triangle. TN: this is the text that accompanies the Vitruvian Man, which is shown below.

This engraving is a 1661 Cellarius' chart that displays Copernicus' heliocentric model of the universe. Except the face on the sun is not in anime style.

An engraving of a steam engine designed by Boulton&Watt.

nær man maethæn lændæs bøtæ foæræ oq qununvi f TN: these are some sort of Nordic runes, and it looks similar to some sort of Medieval runes. This is my guess as to what these runes say, but it is gibberish, as much as I can tell.

These characters, although they seem like traditional Chinese, are actually Tangut script, the unique script for the now extinct Tangut language. No images of Tangut writing seemed to match these particular characters, reading vertically or horizontally, so this may be jibberish.

Some form of cuneiform.

These are Egyptian hieroglyphs.

Likely a diagram of an early computer (like ENIAC) or a patent drawing for another complex machine.