Approximately 5,000 to 6,000 years ago, people began to make clocks: tools that can precisely mark off equal lengths of time. In this book, you will find out about several types of clocks invented throughout history. You will also discover that you can make some of these clocks yourself by following step-by-step instructions. You will even measure your body clock!

"[This book] travels through the past and into the future to explore how humans have measured the passage of time."--P. [4] of cover.

Telling time becomes clear and easy for young readers in this bright and lively introduction to measurements of time. From seconds to minutes, hours to days, exploring what time is and discovering why we need to tell time, helps young readers understand more than 'the big hand is on the one and the little hand is on the two'. Megan Halsey’s playful illustrations depict imaginative digital and analog clocks that range in design. With the help of a whole lot of clocks, a dash of humor, and a few familiar circumstances, learning to tell time is a lot of fun. It's about time.

Harry Chase Brearly in this book gives a detailed description of the history of timekeeping from the stone age through the invention of modern clocks and watches. He described so many important parts of technologies of time-telling devices such as water clocks with the explanation of essential parts that makes up the mechanism of clocks. This book also covers the idea and philosophy of time.

Travel through time with the maestros as they explore the amazing history of timekeeping! Did you know that there is more than one calendar? While the most commonly used calendar was on the year 2000, the Jewish calendar said it was the year 5760, while the Muslim calendar said 1420 and the Chinese calendar said 4698. Why do these differences exist? How did ancient civilizations keep track of time? When and how were clocks first invented? Find answers to all these questions and more in this incredible trip through history.

More than a simple chronology, this volume explores the technical resources used to measure time—solar, hydraulic, mechanical, or electrical—just as it explains the key factors behind the major breakthroughs in the science of horology. From ancient astronomical observatories to atomic clocks, instruments for telling time have always been closely linked to the cutting-edge sciences of the day, ranging from medicine and navigation to aeronautics. Inventions in timekeeping have been crucial to the organization of human society and to activities such as farming, industry, and trade. Each new development was based on the needs and accomplishments of its day yet spurred further discoveries. Writing a history of time means viewing human genius through the prism of the steady mastery of a crucial technology. The patient, long-term conquest of accuracy has been the result of successive advances from sundial to wristwatch up to the recent exploits of the heirs to this age-old quest, namely master horologists of the twenty-first century.

100 days of multiplication problems. Discover the difference a couple minutes of practice can make. These are reproducible practice sheets to help students learn their multiplication facts and recall them with fluidity. This book focuses on digits 0-12. An answer key is included in the back of this book, so students can easily check their own work.