351. Know the difference between aa and pahoehoe
Completed May 1998
I learned this as part of a physical geography class that I took in college, when we learned all about volcanoes. They’re Hawaiian words for different types of lava. Aa (pronounced ah-ah) is cooler, and therefore thicker and blockier. Pahoehoe (pronounced pa-ho-ee-ho-ee) is hotter and flows smoothly.