The Dorling Kindersley Big Book of Knowledge is an exciting new approach to learning through pictures and words. With enchanting photographs detailed illustrations and clear text it introduces children to a wealth of knowledge and encourages them to look further and unearth more of the amazing secrets of our world. Fascinating Facts Did you know that the world's largest cave could hold 800 tennis courts? Did you know that a rodent's front teeth never stop growing? Did you know that it takes about 22 litres of milk to make just one kilogram of butter? These amazing facts and thousands more are all contained within the Big Book. A First Reference Source The Big Book is an ideal first reference source of nature science and the world in which we live. Plants and animals machines and transport science and industry people in the past music and the arts life around the world today - all these and more can be looked up in this ideal first reference book.