The Big Book of Secrets and Mysteries for Boys

Do you want to be known among your friends as a true expert in the most important "boyish" questions? Then you need to learn some secrets without which you won't be able to surprise them, unfortunately. How to stand up... for yourself while remaining gallant and well-mannered? How does a lie detector work? How to read an invisible message? How to charge a battery? What is an azimuth and how to calculate it? How to create a photofit? How to make a compass, a phone, or a watch with your own hands? And finally, what is the secret of the famous deductive method? "How difficult!" you might exclaim. And you would be wrong! Thanks to this beautifully illustrated book, you will overcome any difficulties. It will reveal all the "boyish" secrets and help you master many useful skills. For middle school age.