I recently was able to look at the Register of Seamen's Tickets 1845-1854 (LDS microfilm 1482525), which included the ticket (no. 56694) for one William Rich of Bridgwater, Somerset. I hoped it would answer the question of how my great great grandfather William Rich reached Australia.
Unfortunately, it didn't help me - my William Rich was born in about 1832. The William Rich of seamen's ticket 56694 was born in 1818 and first went to sea as an apprentice in 1835. Shame. So my William Rich must have swum here after all!