HSwMS John Ericsson HSwMS " John Ericsson " was the lead ship of the monitor s built for the Royal Swedish Navy in the mid - 1860s . She was designed under the supervision of the Swedish - born inventor , John Ericsson , and built in Sweden . " John Ericsson " made one foreign visit to Russia in 1867 , but remained in Swedish or Norwegian waters ( at the time , Sweden and Norway were united in personal union ) for the rest of her career . The ship was reconstructed between 1892 and 1895 , but generally remained in reserve . She was mobilized during World War I and sold in 1919 for conversion to a barge . Design and description . The " John Ericsson " - class ironclad s were designed to meet the need of the Swedish and Norwegian navies for small , shallow - draft armored ships capable of defending their coastal waters . The standoff between and the much larger during the Battle of Hampton Roads in early 1862 roused much interest in Sweden in this new type of warship as it seemed ideal for coastal defense duties . John Ericsson , designer and builder of the " Monitor " , had been born in Sweden , although he had become an American citizen in 1848 , and offered to share his design with the Swedes . In response they sent Lieutenant John Christian d ' Ailly to the United States to study monitor design and construction under Ericsson . D ' Ailly arrived in July 1862 and toured rolling mills , gun foundries , and visited several different ironclads under construction . He returned to Sweden in 1863 having completed the drawings of a " Monitor " - type ship under Ericsson ' s supervision . The ship measured long overall , with a beam of . She had a draft of and displaced . " John Ericsson " was divided into nine main compartments by eight watertight bulkheads . Over time a flying bridge and , later , a full superstructure , was added to each ship between the gun turret and the funnel . Initially her crew numbered 80 officers and men , but this increased to 104 as she was modified with additional weapons . Propulsion . The " John Ericsson " - class ships had one twin - cylinder vibrating lever steam engines , designed by Ericsson himself , driving a single four - bladed , propeller . Their engines were powered by four fire - tube boiler s at a working pressure of . The engines produced a total of which gave the monitors a maximum speed of in calm waters . The ships carried of coal , enough for six day ' s steaming . Armament . The lead ship , " John Ericsson " , carried a pair of smoothbore Dahlgren muzzleloader s , donated by John Ericsson , in her turret . Each gun weighed approximately and fired solid shot and a explosive shell . The massive shells took 5 – 6 minutes to reload . They had a maximum muzzle velocity of . These guns were designated as the M / 65 by the Swedes . In 1877 " John Ericsson " received a pair of 10 - barreled M / 75 machine gun s designed by Helge Palmcrantz . Each machine gun weighed and had a rate of fire of 500 rounds per minute . Its projectiles had a muzzle velocity of and a maximum range of . These guns were replaced during the 1880s by the 4 - barreled M / 77 Nordenfeldt gun , which was an enlarged version of Palmcrantz ' s original design . The gun had a rate of fire of 120 rounds per minute and each round had a muzzle velocity of . Its maximum range was . " John Ericsson " was rearmed in 1881 with two M / 76 rifled breech loader s , derived from a French design . They weighed and had a muzzle velocity of . Coupled with the increased elevation of 11 . 29° , this gave them a range of . Armor . The " John Ericsson " - class ships had a complete waterline armor belt of wrought iron that was high and thick . The armor consisted of five plates backed by of wood . The lower edge of this belt was thick as it was only three plates thick . The maximum thickness of the armored deck was in two layers . The gun turret ' s armor consisted of twelve layers of iron , totalling in thickness on the first four monitors . The inside of the turret was lined with mattresses to catch splinters . The base of the turret was protected with a glacis , high , and the turret ' s roof was 127 millimeters thick . The conning tower was positioned on top of the turret and its sides were ten layers ( ) thick . The funnel was protected by six layers of armor with a total thickness of up to half its height . Service . " John Ericsson " had her keel laid down in June 1864 and was launched 17 March 1865 . She was commissioned on 13 November 1865 . In July 1867 Crown Prince Oscar , later King Oscar II , inspected " John Ericsson " , , , the steam frigate s " Thor " and , and the Norwegian monitor in the Stockholm archipelago before they departed for port visits in Helsingfors , later known as Helsinki , and Kronstadt in August , where they were visited by Grand Duke Konstantin Nikolayevich of Russia , head of the Imperial Russian Navy . This was the only foreign visit ever made by the ship . Generally the monitors were kept in reserve for most of the year ; only being commissioned for two to four months during the summer and fall . " John Ericsson " kept up the pattern between 1865 and 1873 , but remained in reserve afterward until 1882 . She was rearmed with two M / 76 guns in 1881 while her original Dahlgren guns became part of the Ericsson monument at Filipstad . She was reactivated in 1882 and 1883 , but only sporadically thereafter . The ship was reconstructed between 1892 and 1895 ; her gun turret was fixed in place and modified to serve as a barbette for her two new Bofors M / 89 guns . The guns could depress to −5° and elevate to + 13° , and they had a firing arc of 290° . Two Nordenfeldt M / 92 quick - firing gun s were also added on the superstructure . The ship ' s boilers were replaced by new cylindrical ones that had a working pressure of and " John Ericsson " reached on sea trials on 14 May 1901 . During the early 1900s the two 25 - millimeter machine guns were removed and four , later six , more 57 - millimeter guns added to the superstructure . The ship was assigned to the Karlskrona local defense force during 1913 – 18 , and she was sold to the Gotland Cement Company ( ) in November 1919 . The company converted her to a barge and used her for the next forty years ; her final fate is unknown .