Enrichment, burnable poison, and self-poisoning

 "Difficulty shows what men are.  Therefore when a difficulty falls upon you, remember that God, like a trainer of wrestlers, has matched you with a rough young man.  Why?  So that you may become an Olympic conqueror; but it is not accomplished without sweat." - Epictetus

Jefferson Mystery Clocks

 Be not disgusted, nor discouraged, if thou dost not succeed in doing everything according to right principles; but when thou hast failed, return back again, and be content if the greater part of what thou doest is consistent with man's nature, and love this to which thou returnest." - Marcus Aurelius

Shop Bathroom Water Heater

 "Confine yourself to the present" - Marcus Aurelius

Determining the charge of an electron

 "Take the shortest route, the one that nature planned - to speak and act in the healthiest way.  Do that, and be free of pain and stress, free of all calculation and pretension." - Marcus Aurelius

Mid-August

 "Freedom is the only worthy goal in life.  It is won by disregarding things that lie beyond our control" - Epictetus