Builder’s Drawing of Wren and Lark
One item from the Merseyside Maritime Museum exhibition, Ships built in Liverpool for the American Civil War:
This cross-section is very similar to an earlier Laird-built paddle steamer, Denbigh. Around the outer edge of the hull are notations of plate thicknesses, and the column at right tallies up weights. The spacing of the frames at 21 inches is a bit more than the standard 18 inches, suggesting a willingness to trade structural strength for a saving of weight. We read recently about Wren‘s eventful arrival here in early February 1865; Lark‘s story will be told in due time.
The drawing above, rendered in three dimensions, would be something like this: