英语翻译18.Samuel Langley wasn't married and have no children.He

英语翻译
18.Samuel Langley wasn't married and have no children.He spent all his time on scientific projects.One project was a personal dream.He wanted to design and build a flying machine.
Before he left the Allegheny Observatory,he had begun to investigate the possibility.There was little earlier research to guide him.Consequently,he studied the flight of birds and the movement of air over curved surfaces.Langley's interest in the possibility of flight continued when he went to the Smithsonian.He began to build very small airplanes using the rules of flight he had discovered.
On May 6,1896,Langley's first unmanned plane was launched from the top of a houseboat floating on the Potomac River south of Washington.It flew more than nine-hundred meters and landed softly on the water.
In November of that year,another of Langley's planes made an even longer flight.These were the first free flights of heavier-than-air machines ever made.After the flights,Langley said he had completed the work he wanted to do.He had shown that mechanical flight was possible.Other people,he said,would have to develop the idea further.
Shortly after Langley's successes with his model planes,the United States entered a war with Spain.The American government became interested in developing a fullsize plane that could carry a person.Such a plane could be used to observe the enemy.Balloons had been used to do this for a hundred years.But balloons were difficult to fly.
Therefore,with the support of President William McKinley,the War Department gave Langley fifty-thousand dollars to build a full-size plane.Langley and an engineer,Charles Manley,began designing it.They worked for five years.
必须自己翻译啊 不要

塞缪尔.兰德里将毕生都献给了科学事业,他终生未娶,也没有孩子.他想设计、制造一个飞行器,这是他的一个梦想.
在离开阿勒格尼天文台之前,他已经着手研究这种可行性.此前没有任何这方面的研究供其参考,他持续观察着鸟类飞行、研究空气对曲面的运动.他去了史密森学会后,兴趣仍然放在研究飞行器的可行性上,他利用自己发现的鸟的飞行规律着手建造了一些很小的飞行器.
1896年5月6日 兰德里制造的第一架无人驾驶飞行器从飘在水面的游艇甲板起飞平稳降落到位于华盛顿南部的波托马克河水面上.飞行距离超过900米.
是年11月另一架兰德里制造的飞行器问世,它甚至比原来的那架更长.这是世界上第一架重量超过通风机的自由飞行器.甚至以后所造的飞机再也没有出现过这种重量.兰德里说他已经完成了研发,他已经向世人展示了这种机械飞行的可行性,他想要制造它.他还说；他想和另外一些人进一步完善自己的想法.
兰德里成功制造飞机模型不久,美国与西班牙开战,美国政府对研制一种标准型可载人飞行器产生了兴趣.比如可用它来侦察敌情,过去一百年以来气球一直充当这个角色,但是,气球毕竟很难飞起来.
因此,兰德里的研发得到了时任美国总统威廉.麦金利的支持,国防部拨款5万美元用于兰德里研发标准型飞机.于是兰德里和另外一个工程师查尔斯.曼利着手设计它.他们一起干了五年.