Da Vinci invented the manuscript - spiral helicopter

https://www.youtube.com/watch?v=eKTdhRBH8DM&feature=youtu.be Fascinated by the flight phenomenon, Da Vinci made a detailed study of bird flight. At the same time, he planned several flying machines, including this helicopter with four manpower (but it would not work because the body itself would also rotate). This model uses a beveled gear painted inside his manuscript to create a perfect replica version. When turning the lower handle, you can watch the smooth rotation of the upper screw shed. This is a DIY component that understands gears and flight principles, allowing the design of Davinci's clever and flying enthusiasm helicopters to reappear in the world and to play the best of edutainment. "About Da Vinci Manuscripts" Leonardo da Vinci took notes every day for the rest of his life and wrote it in his own unique mirror image (starting from the bottom right corner of each page, from right to left, and writing up and down). Because his notes are for his own reference only, the structure is scattered, the fonts are scribbled, and there are no punctuation marks. Although some speculated that Da Vinci was in order to keep secrets, a more plausible view was that mirroring and writing was only a matter of left-handed writing. Da Vinci's research in science and engineering is as impressive as his artwork. About 13,000 pages of notes and paintings in the manuscript are all made up of records of mixed arts and sciences. These records come from Da Vinci's observations and his constant creation during his travels. Da Vinci manuscripts are divided into several categories: painting/engraving/architectural/physiological/anatomical/zoological/astronomy/geography/philosophy/story/letter. These manuscripts of different sizes were originally distributed in the hands of friends after his death. They are now mainly collected in museums, library rooms or libraries around the world. Product specification: ► Product size: 22.8 x 22.8 x 35.5 cm ► Material: logs, metal, cloth, string, with 5ml viscose ► Canadian Design Made in Taiwan Precautions: ► Please stay away from the fire ► Please take care of children swallowing small parts ► This product is suitable for use over 9 years old ► Please note that the appreciation period is not equal to the trial period. If there is an assembly, it will affect your return rights. Please keep the package intact when returning for replacement. If there is damage, it will be difficult to return. ► Books, merchandise, gifts, etc. that are covered with plastic film are subject to the return policy. If the film has been unsealed, no returns will be accepted.