Search results
Our web pages use cookies—information about how you interact with the site. When you select “Accept all cookies,” you’re agreeing to let your browser store that data on your device so that we can provide you with a better, more relevant experience.
airline industry. airline industry, the business of transporting paying passengers and freight by air along regularly scheduled routes, typically by airplanes but also by helicopter. Ferdinand Graf von Zeppelin set up the first commercial airline in 1912, using a form of the dirigible to transport more than 34,000 passengers before World War I.
May 23, 2018 · Jim Crow was the colloquial term for forms of systematic discrimination employed by whites against African Americans from the second half of the nineteenth century through the first half of the twentieth. The expression insinuates the legal components of the color line (e.g., Jim Crow laws ), but also encompasses the cultural and symbolic ...
tar and pitch. tar and pitch, viscous, dark-brown to black substances obtained by the destructive distillation of coal, wood, petroleum, peat, and certain other organic materials. The heating or partial burning of wood to make charcoal yields tar as a byproduct and is an ancient method for the production of both tar and pitch.
Porifera pōrĭfˈərə [ key] [Lat.,=pore bearer], animal phylum consisting of the organisms commonly called sponges. It is the only phylum of the animal subkingdom Parazoa and represents the least evolutionarily advanced group of the animal kingdom. All adult sponges are sessile (nonmotile), and nearly all are marine; there are six families ...
humidity. humidity, moisture content of the atmosphere, a primary element of climate. Humidity measurements include absolute humidity, the mass of water vapor per unit volume of natural air; relative humidity (usually meant when the term humidity alone is used), the ratio of the actual water-vapor content of the air to its total capacity at the ...
