Πάππος ὁ Ἀλεξανδρεύς (Pappus of Alexandria), ca. 290-350 A.D., was a Greek mathematician known for his hexagon theorem in projective geometry. Almost nothing is known about his life except for what can be found in his own writings, many of which are lost. Pappus apparently lived in Alexandria. The Collection, his best-known work, is a compendium of mathematics in eight volumes, the bulk of which survives. It covers a wide range of topics including geometry, astronomy, and mechanics. (The image is the title page of a Latin translation from 1588.) Pappus time is considered one of stagnation in mathematics, where, to some, he stands out as a remarkable exception and, to others, as an exemplar of ills that halted the progress of Greek science. His work became influential in the late Renaissance and Early Modern periods. His lifetime is uncertain, but we know he was active in 320, because he recorded his calculation of the "the eclipse in Tybi in 1068 after Nabonassar." That converts to this date 1,706 years ago, in the year 320. Credit: https://w.wiki/EMhZ Image: https://w.wiki/dfKN Federico Commandino 1588 Public Domain Today I completed the route I planned to ride three days ago, but cut short due to the extreme heat, over 90 degrees much of the time. Today, I started about 7:30 a.m., when it was quite cool, and it went over 80 degrees only briefly. I climbed several familiar hills today, and all felt easier than I remembered. And today was my fastest time ever going up Sepulveda from Sherman Oaks through the tunnel. That's only 425 feet in 2.2 miles, so not all that hard, but it's a climb I've done many times, so I'm happy to claim a new record. I don't always caption the photos, but I'll try to do it this time, because they capture stuff I haven't seen for a few months or even longer!