Rifled muzzle-loading guns on a British warship, possibly <a href="https://en.wikipedia.org/wiki/HMS_Opal_(1875)" class="extiw" title="en:HMS Opal (1875)">HMS Opal</a>, in Sydney.
Unknown author<span style="display: none;">Unknown author</span>
CC BY 2.0
<p>NSW State Records : Digital ID: 4481_a026_000460.jpg : <a rel="nofollow" class="external free" href="http://investigator.records.nsw.gov.au/asp/photosearch/search.asp?digitalid=4481_a026_000460&amp;B1=Search">http://investigator.records.nsw.gov.au/asp/photosearch/search.asp?digitalid=4481_a026_000460&amp;B1=Search</a>
</p>
<br>This version from Flickr : <a rel="nofollow" class="external free" href="https://www.flickr.com/photos/state-records-nsw/4312110589/">https://www.flickr.com/photos/state-records-nsw/4312110589/</a>