Las estaciones del ferrocarril subterráneo (Depots of the Underground Railroad)

"Some things are so huge or so old that it's hard to wrap your mind around them. But what if we took these big, hard-to-imagine objects and events and compared them to things we can see, feel and touch? Instantly, we'd see our world in a whole new way." So begins this endlessly intriguing guide to better understanding all those really big ideas and numbers children come across on a regular basis. Author David J. Smith has found clever devices to scale down everything from time lines (the history of Earth compressed into one year), to quantities (all the wealth in the world divided into one...

Wind Power: A waving flag, blowing leaves, a kite soaring through the skyall are moved by wind power. Wind is also our fast-growing source of energy. Find out how wind forms and the different ways we may use it in the future.

Amusing And Engaging Text Describes How The Color Of An Animal Can Ensure Its survival. Provides Examples Using A Variety Of Animals.

La física y la química son dos ciencias fascinantes e imprescindibles para comprender el funcionamiento del mundo que nos rodea, pero que a menudo no han conseguido ser bien entendidas por los estudiantes. El propósito de este atlas es presentar la física y la química de forma clara, amena e interesante, huyendo siempre que sea posible de la carga matemática y de las fórmulas que no sean imprescindibles. En la elaboración de este libro se ha hecho un importante esfuerzo por simplificar las explicaciones y evitar la sobrecarga de datos, aunque se han subrayado datos curiosos y...