Irene and Vernon Castle posed as instruction for dancing their version of the tango. From their 1914 book "Modern Dancing" published by The World Syndicate Co. by arrangement with Harper &amp; Brothers.
<bdi><a href="https://en.wikipedia.org/wiki/en:Irene_Castle" class="extiw" title="w:en:Irene Castle"><span title="American actress and dancer (1893-1969)">Irene Castle</span></a>
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