Advertisement for W. Bollman &amp; Co., Baltimore, Maryland, in the <i>Railroad Advocate,</i> August 1855.<br>
Original caption: "Figure 12.—Advertisement in the Railroad Advocate, August 1855."
J.H. Tegmeyer
<p>Vogel, Robert M. (2010-10-20). <i>The Engineering Contributions of Wendel Bollman.</i>
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