In 1755, having risen to be a mate, Cook joined the Royal Navy, and after four years' service was, on the recommendation of Sir Hugh Palliser, his commander, appointed master successively of the sloop Grampus, of the Garland and of the Solebay, in the last of which he served in the St. Lawrence.
Tap Bolt vs Cap Screw. What is the difference between a tap bolt and a cap screw? A tap bolt is (typically) a fully threaded hex bolt, while a cap screw is (typically) a hex head bolt that will be installed by turning the head of the bolt (screw) instead of tightening it with a nut.
1 Fully Threaded Metric Bolts: These bolts have threads running the full length of the bolt, from the underside of the head to the tip.  Partially Threaded Metric Bolts: Starting at the underside of the head, these bolts have an area that is free of threads.