Parkinson &amp; Frodsham <a href="https://en.wikipedia.org/wiki/transit_instrument" class="extiw" title="w:transit instrument">transit instrument</a>, Liverpool, circa 1838. From the <a href="https://en.wikipedia.org/wiki/Ladd_Observatory" class="extiw" title="w:Ladd Observatory">Ladd Observatory</a> history of science collection.
<bdi><a href="https://en.wikipedia.org/wiki/en:Ladd_Observatory" class="extiw" title="w:en:Ladd Observatory"><span title="astronomical observatory at Brown University">Ladd Observatory</span></a>
</bdi>
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<span class="int-own-work" lang="en">Own work</span>