“He thought that maybe, just maybe, you could make gold by letting more than 5500L of human pee sit until it smelled horrible, boiling that rotten urine down to a syrup, heating it until a red oil came out, letting the rest separate into two parts as it cooled (one black and spongy, and one beneath it more grainy and salty), adding the oil back into the spongy upper part of his cooled urine paste and discarding the rest, heating it again for sixteen hours, and then feeding the gases this produced through water. This does not make gold, but it does produce what Brand called “cold fire”: a glow-in-the-dark compound that contains the phosphorus naturally found in urine.” HumorScienceNonfiction Book:How to Invent Everything: A Survival Guide for the Stranded Time Traveler Source: How to Invent Everything: A Survival Guide for the Stranded Time Traveler
“Trigonometry lets you use some known quantities about a triangle to determine its unknown quantities, we will interrupt ourselves right now because we can already hear you muttering, “Come on, when am I ever gonna use this?” Here is when you are going to use this: in navigation, astronomy, music, number theory, engineering, electronics, physics, architecture, optics, statistics, cartography, and more. You already need it just to build a proper sundial, hence the unofficial slogan of trigonometry: “Okay, fine, I guess this is actually pretty important after all.” Trigonometry deals only with right triangles (triangles with two edges that meet at 90 degrees, and we mark that angle with a little square), but since any non-right triangle can be divided into two right triangles (try it; it’s true), that’s not going to be a problem.” HumorScienceKnowledge Book:How to Invent Everything: A Survival Guide for the Stranded Time Traveler Source: How to Invent Everything: A Survival Guide for the Stranded Time Traveler
