The SS Clan Leslie was built by Clan Line Steamers Ltd., which was founded in 1878 by Charles Cayzer (the first of the Cayzer Baronets).
The company operated in London and Glasgow. The SS Clan Leslie was one of the company’s fleet of freighters and passenger liners, most of which were named after Clans.
The SS Clan Leslie was Built in 1902 and was sunk by an Austro-Hungarian torpedo November 4, 1916, about 200 miles Southeast of Malta. The ship was returning to London from Bombay (Mumbai), India. She was not carrying a military cargo. Three hands lost their lives.
The submarine that launched the attack was the German Built UB-43 which was sold to the Austrians and renumbered the U-43. As such, she sank 22 ships between her launch on April 8, 1916 and being decommissioned on July 21, 1917. She was one of six Austro Hungarian submarines assigned to the Mediterranean. The U-43 was ceded to France as war reparations and broken up by the French after the war.
More can be learned about the U-43 on Wikipedia. Cayzer and Irvine Ltd. lost 69 ships, many named after Clans, during the First World War.