The German spar torpedo boats according to the Australian newspaper The Sydney Mail and New South Whales dated Saturday 6 January 1872

An item referred to the German Bromberger Zeitung which published a letter from Danzig supplying some details about 3 boats for the German navy under the title German Naval Invention. “Three boats are just now in course of construction in Devrient’s dockyard, the destination of which is to place torpedoes under, and thus to destroy, an enemy's ships. These boats are built almost entirely of iron, and, being about 60 feet long and only six or seven broad, they are nearly the form of a fish. The deck is not flat, but round, so as to be little exposed to danger from an enemy's shot. While employed in active operations no one will be visible on board. Contrary to the usual system, these boats will be steered from the bows  and on the deck, above the rudder, there is a slight elevation to allow the steersman to stand on his feet, and a small opening about an inch wide to serve him-as a look-out. As they are intended to operate close to an enemy's vessels, the armour will be as thick as is consistent with high speed. The most curious part of the invention, perhaps, is that the tiny screw steamers, or barcassen (long-boats) as they are called, use petroleum as fuel, which is contained in a number of iron receptacles in the stern, of sufficient thickness to be impervious to projectiles. The chimney is so small that it can scarcely in any case be hit. A narrow gallery, about a foot broad, and enclosed by an iron chain, runs round the boat. The machines have all been furnished by Stockel and Wagenknecht, so that the boats have been produced in Danzig from stem to stern. The hold for the torpedoes is in the middle of the boat, as well as the quarters of the crew. One of the barcassen has already been launched, and is only waiting for her engine. The two others are still on the stocks”.(1)

Note

1. German warships 1815-1945. Volume I. Erich Gröner, revised by D. Jung and M. Maass. The invention consisted of spar torpedo boats Nos. I-III built by Devrient, Danzig between 1871-1872 with as dimensions 20.3 x 3.30 x 1.9 metres.