For more than two centuries, almanacs have played a central role in American life, especially in rural and agricultural ...

Though it authorized our nation's earliest imperialistic land grab outside our continent, the 1856 Guano Islands Act is little known today. The act stated that the United States could claim any island ...

Katie has a PhD in maths, specializing in the intersection of dynamical systems and number theory. She reports on topics from maths and history to society and animals. Katie has a PhD in maths, ...

If you enjoyed this article, I’d like to ask for your support. Scientific American has served as an advocate for science and industry for 180 years, and right now may be the most critical moment in ...