El ferrocarril transcontinental (The Transcontinental Railroad)

People today refer to the Midwestern and prairie states as flyover country. During the Civil War, crossing those areas was the biggest obstacle in uniting the East and West Coasts of our divided nation. An act of Congress in 1862 authorized the Central Pacific and the Union Pacific railroad companies to build a railroad that would link the coasts. Seven years later, on May 10, 1869, an overwhelmingly immigrant labor force completed the task when a rail line was join in Promontory, Utah. The states had become united at last.

Culmina con este volumen la trilogía de poesía religiosa «Hombre y Dios». Para esta última antología se ha elegido Europa, incluyendo la del Este, aunque el «telón» impidió, durante un largo tiempo, la publicación de este tipo de poesía en algunos países. La selección de poemas aquí recogidos se-rá, quizá, para algunos lectores el único medio de otear las intuiciones poéticas de la Europa del siglo XX. Hay textos fragmentarios, hecho que responde al deseo de ajustarse a la elección inicial de la obra, y se ha optado por presentar en forma bilingüe los poemas escritos en...

Need it or want it — what's the difference? Needs are things people cannot live without, such as food, water, and shelter. Let's explore the differences between the concepts of needs and wants! The Me Pregunto (I Wonder) series is perfect for young learners in prekindergarten through grade 2. These 16-page books give readers an accessible introduction to nonfiction reading. Color photographs and fun, factual examples will grab the attention of young readers and help strengthen reading comprehension skills.

The rock cycle has been taking place for millions of years. However, geologists have only known about this phenomenon for about 300 years. Young terrestrial explorers are introduced to different types of rocks, where in the cycle these rocks fit, and where in Earth's layers each step takes place. Fact boxes provide readers with fun additional information. A diagram helps readers make sense of the new information they're learning.

¿Sabías que la gente puede excavar y utilizar el calor de la Tierra para producir energía? Esta energía geotérmica puede alimentar tu computadora y calentar o enfriar tu hogar. Pero, ¿cómo se obtiene exactamente? ¿Y cuál es el impacto sobre el medioambiente? Lee este libro para aprender todo sobre la energía geotérmica. Did you know people can dig underground and use Earth's heat to make energy? This geothermal energy can power your computer and heat or cool your home. How exactly do we get it, though? And what is the impact on our environment? Read this book to find out all about...