torpedoboats

There is an error in the caption ;-(( Speed is sometimes incorrectly expressed as "knots per hour", which is in fact a measure of acceleration. See Wiki page for Knot = speed. This old fogey cannot paste a working link to the right page ;-((

This may be one of the TB 63 series second class torpedo boats procured by the British Royal Navy from the Herreshoff Company, Bristol, RI, USA. According to _The Sail & Steam Navy List: All the Ships of the Royal Navy, 1815-1889_, By David Lyon and Rif Winfield, these were the only steam powered vessels purchased by the RN from an overseas provider during the 19th Century.

Beautifully sleek

it's called "lightning?"

L oso Indeed! It was originally called the HMS Lightning, and later was renamed to "Torpedo Boat No. 1". It was eventually broken up in 1896.

Odd that the photo caption identifies her as a second-class torpedo boat, because Lightning and her near sisters were classified as first-class torpedo boats when they were first built. At that time, the Royal Navy defined first-class boats as those capable of operating on their own from a harbor or coastal base, while the second-class boats, which were even smaller than Lightning, were designed to be carried by larger ships and lowered into the water when needed. However, I'd guess that the Lightning-type boats would have been demoted to second-class status as newer, larger boats came into service, and this photo may have been printed during that period, even though it probably dates from when Lightning was first built (she doesn't even have her torpedo gear fitted). Incidentally, though she doesn't look like much to modern eyes, Lightning was considered a very fast boat when she was built. She could outrun the fastest ocean liners of her day, and these were among the fastest ships afloat.