Completed locomotive boiler. N.B. The opening in the front of the firebox casing is special to this particular boiler, and does not exist in ordinary boilers of standard construction.
<a href="https://en.wikisource.org/wiki/Author:E._L._Ahrons" class="extiw" title="s:Author:E. L. Ahrons">E. L. Ahrons</a>
<i>Original:</i> Steam Locomotive Construction and Maintenance (1921) p. 25, Fig. 7,<br>Previously published in E. L. Ahrons’ <i>The Development of British Locomotive Design</i> (1914).<br><i>Scan:</i> Internet Archive – <a rel="nofollow" class="external free" href="https://archive.org/details/steamlocomotivec00ahrorich">https://archive.org/details/steamlocomotivec00ahrorich</a>