Coverpage of "On Aerial Locomotion", by Matthew Piers Watt Boulton, published in 1864. This paper described methods of aircraft propulsion, among several other items and designs. Boulton then patented ailerons in 1868.
<bdi><a href="https://en.wikipedia.org/wiki/en:Matthew_Piers_Watt_Boulton" class="extiw" title="w:en:Matthew Piers Watt Boulton"><span title="British classicist (1820–1894)">Matthew Piers Watt Boulton</span></a>
</bdi>
1864
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