Vignette inscribed: “Merlin & Firefly struck by infernal machines”. Refers to an occasion when Admiral Dundas, in the ‘Merlin’, was surveying Sveaborg (Helsinki) on 9 June 1855 and struck by Russian mines (see ILN, 15 Sep 1855, p.340); she was supported by the ‘Firefly’, who was also struck. This is considered the first instance of successful mining in naval warfare.

The three-masted ‘Firefly’ is shown on the left; the two-masted ‘Merlin’ further back on the right.