Jamison sailed for Australia in May 1787 from Portsmouth, southern England. He arrived safely with the fleet at their final destination, the site of the future City of Sydney, in January the following year. Shortly after their arrival, the commander of the fleet, Governor Arthur Phillip, sent a detachment of guards, convicts and naval personnel – including Jamison – from Sydney Cove to Norfolk Island. They were under orders to plant an ancillary colony on the island, which is located in the Pacific Ocean, roughly halfway between Australia and New Zealand.