James Cunningham Blacker was a crew member of the famous Confederate battleship, the CSS Shenandoah. He is not listed by many as having joined the CSS Shenandoah crew from Melbourne, Australia due to the fact that he was aboard a ship called the Saxonia that was docked in Melbourne at the time. Its average passage time from Liverpool, England to Queenstown and then on to Boston was said to be about nine days. Blacker was in fact a Captain in the English merchant service and was said to have abandoned his ship in Melbourne to join the crew of the Shenandoah. He was not actually from Australia, but was berthed aboard a ship docked in Melbourne at the time and was appointed directly, as an officer of the Shenandoah as the Captain's clerk, when he choose to join the crew. He did, however, join the Shenandoah crew ‘from' Melbourne, Australia. He was residing there, when like a number of others in the area, he heard that the Confederate Cruiser, the "CSS Shenandoah", had arrived in Port Phillip Bay, off Melbourne, on January 25, 1865. Following hundreds of others, Collins made his way to the Williamstown docks where the "Shenandoah' had been berthed for repairs, and stole aboard on the night of February 17, 1865; even though it had been prohibited by local officials. Once on board he met with crewmembers that quickly hid him out in the hold of the ship where he remained in hiding, aided by crewmembers, until the "CSS Shenandoah" had weighed anchor and moved out of Australian waters.

He was also listed among those designated as Confederate Marines aboard ship. He remained aboard the "Shenandoah" for the remainder of its historic voyage; until it was surrendered by Lieutenant Waddell, on November 6, 1865, to British Captain Paynter, commanding her Majesty's ship "Donegal, in Liverpool, England. The crew being paroled after its surrender took up temporary residence in Williamstown. It is not known if Collins returned to America, but in all likelihood he returned to his former home in Australia.