Yes, but both are slang units of distance and diameter. The eyes of typical gnats tend to have diameters similar in size to a hair’s breadth—roughly 100–150 micrometers. An item would have to be very short in order to be gnat’s eye in length! A hair’s breadth is an informal unit of distance: it is used to denote a measurement of approximately 70 to 100 micrometers in diameter, or 0.1 millimeter, which is similar in thickness to real human hair.
Estuaries are bodies of water along the beaches that are formed when freshwater from rivers flows into and mixes with saltwater from the ocean. Tides may rise and fall in the estuary, making this area a unique ecosystem rich in nutrients. Only certain types of plants, such as saltwort, eelgrass, and saltgrass can grow there, and few animals can live their entire lives there. However, mud shrimp, certain types of mussels, and the Western sandpiper all call estuaries home.
The ancient Greeks believed a blessing might prevent evil from entering your body during its unguarded state while you sneeze. Our tradition comes from the black plague of 1665, when sneezing was believed to be one of the first symptoms of the disease. Infection meant certain death, and so the symptom was greeted with the prayer, “God bless you,” which through time has been shortened to “Bless you!”
The Greek philosopher Aristotle proposed that the heavens were composed of 55 concentric, crystalline spheres to which the celestial objects were attached and which rotated at different velocities, with the Earth at the center. People believed this for almost 2000 years, until Polish astronomer Nicolai Copernicus proposed that the Sun, not Earth, was the center of the solar system. His model, called a heliocentric system, said that Earth is just another planet (the third outward from the Sun), and the Moon is in orbit around Earth, not the Sun. While this might be true of our solar system, astronomers cannot see the whole universe through their telescopes, so no one knows where the true “center” of it lies.
Scientists have found and described more than 275,000 kinds of plants, but they believe that many more are yet to be discovered. Plants vary greatly in size and appearance. Some, like single-celled algae, are so small that you can only see them with the help of a microscope. Others, like giant sequoia trees, are so big that you cannot even see the tops of them. Plants are very different from one another because they have developed features—over millions of years—to help them live in the world’s many different environments.
White clothes are good reflectors and bad absorbers of heat, whereas dark or black clothes are good absorbers of heat. Therefore, white clothes are more comfortable because they do not absorb heat from the sun rays.
Wood contains a complex mixture of gases and tar forming vapors trapped under its surface. These gases and tar vapors escape, making a cracking sound.
It’s a myth that the camp followers of Union General Joseph Hooker gave us the popular euphemism for a prostitute. It’s true they were called “Hooker’s division,” or “Hooker’s reserves,” but the word predates the American Civil War as, of course, does the profession. It first appeared in 1845 as a reference to an area of New York known as “the Hook,” where ladies of the night could be found in abundance.
A dozen is a unit of quantity, equal to 12. A baker’s dozen is an informal unit of quantity, equal to 13. Bakers often toss in an extra item for each dozen bought, making a total of 13. This custom is very old, dating at least from the thirteenth century, when the weights and prices of loaves of bread were strictly regulated by royal proclamations called assizes, and bakers could be jailed if they failed to provide fair weight at the listed prices.
The phrase boning up comes from a British teacher of Greek and Latin Who wanted to make life easier for his students. With that goal in mind he translated the Greek and Latin classics into English and then had them published and distributed within his classroom. His name was Mr. Bohn, and his grateful students called this new, speedier method of studying the classics “Bohning up.”