Launoy and Bienvenu’s toy was a rudimentary helicopter with a central shaft, corks at both ends with feathers angled to provide lift as they spun, and a bow (as in bow and arrow) drawn taut by winding its string around the shaft.
给这篇翻译加备注
Havacılığın doğuşu ve ilk kanat prototipleri üzerine yazılmış bir kitaptan alıntıdır. İçinden çıkamadım acil dönüş yapabilen olursa çok sevinirim.İyi akşamlar
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