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本帖最后由 ngsunyu 于 2019-12-2 04:49 编辑
11月在巴黎卢浮宫参观达·芬奇画展。看到意大利米兰安波羅修圖書館(Biblioteca Ambrosiana)借来的达·芬奇的大西洋古抄本(意大利語:Codice Atlantico)中的《飞行器草图》。大西洋古抄本是諸多达·芬奇的手稿集冊中最大的一部,共12卷,1119張,年代分佈為1478年到1519年,包含的類別非常廣泛,有飛行、武器、樂器、數學、植物學等等,讓後人得以一窺达·芬奇多才多藝的思路。(zh.wikipedia.org/大西洋古抄本)
l9 世纪中叶, 在意大利米兰图书馆中找到了达·芬奇在 1483 年写的札记中的一张飞行器草图,草图标明 : 这架飞行器的升力是由旋转着的螺旋桨所产生的。它的主要部件是一个螺旋面,其几何图形相当于桨叶旋转与前进合成运动画出的曲面 ,两个端面间的夹角约 54 °。中间是一个直轴,上面缠绕弹簧来驱动螺旋面旋转。在草图旁边,达芬奇写道:“螺旋桨的骨架应该用像细绳子那样植细的铁丝制成,从圆周到中心距离应该等于八肘(一肘大约等于60厘米)。如果这种装置制造得很好 , 是用结实的帆(其孔眼都用淀粉糊细致地涂过)而制成的, 那么, 我想, 当螺旋桨迅速旋转时它将在空中画出一条旋转的迹线、并向上升起。当你用一根宽而薄的尺子劈开空气 , 那么你就会相信这一点了,这时‘你的手会感到尺子侧面方面的压力。你可以用纸来做一个小模型 , 帆布应该固定在用长而细的芦草轩制成的骨架上。 这个模型的轴和上紧的金属弹簧相连, 如果弹簧松开它就会 使螺旋转动起来。” (http://www.mygeek.cn)
Da Vinci's design is notable because it does not include any bird like features, which were commonly seen in early flying machine designs. This design, also known as the Aerial Screw, measured around 15 feet in diameter and was to have been constructed from linen, reed and wire. Beside the sketches, the artist has scribbled "If this instrument made with a screw be well made – that is to say, made of linen of which the pores are stopped up with starch and be turned swiftly, the said screw will make its spiral in the air and it will rise high". This note is what many modern thinkers have clung to in their attempts to give Da Vinci the credit for the original idea of the helicopter. However, the device he has drawn and described appears to be more similar to a modern microlight. (Leonardo-da-Vinci.net)
意大利郵政在2015年发行了一枚 达·芬奇的《飞行器草图》 郵票。我找不到《飞行器草图》明信片。多虧有第二名意大利邮商制了极限明信片待售。 |
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