Nicol's autobiography was published in 1822, around the time the (American) First Fleet sailor Jacob Nagle was writing up his memoirs (though his didn't surface in print for another 150 years), and there are remarkable parallels in the stories they highlight of their years at sea. Both were involved in naval engagements, both appear (admittedly by their own account) very competent. Nicol though admits to more weaknesses, straying from his religion at sea. Nicol even admits to his relationship with a female convict during the journey to New South Wales on the Lady Julian.
Nagle's New South Wales experience is told in more detail than Nicol. As sailors, both largely confined themselves to their boats in Port Jackson, but Nicol did not have the opportunities (and perhaps curiosity?) to explore the surroundings. Instead, Nicol falls in love - a love that is clearly life-defining for John. On the journey he fell in love with Sarah Whitlam, a convict from Lincolnshire. They had a child, a son that stayed with Sarah when John sailed out of Port Jackson after six weeks. John and Sarah promised to be faithful to one another, and that he would return.
John was true to his word, and spent the next several years trying to devise a scheme to join a ship sailing for a port, through which he could connect with a ship back to New South Wales. Destiny was not on his side, and the timing was never right. John returns to Sarah again and again in his subsequent narrative. A year or so after leaving Sydney, he intersected with another ship that had left Sydney and had an escaped convict aboard. This convict (not named) eventually spoke with John and told him Sarah had sailed for Bombay.
John was devastated and states that he then set his sights on a ship for Bombay to find her. The records do not bear this out, and in fact while John pined, Sarah had married another man the DAY AFTER he left Sydney. Michael Flynn's excellent 'The Second Fleet' biography of Sarah Whitlam states that she then spent time on Norfolk Island, and after gaining her freedom did sail for England via India. Nothing more is known of Sarah or their son John. Amazingly, John Nicol visited Sarah's home town when in England again, and her parents indicated they had not heard any more of her. It must have been remarkable to have a sailor arrive on their village doorstep with tales of their convict daughter from the other side of the globe, and the grandchild born out of wedlock that they did not know existed.
That romantic thread, that John relayed through his autobiography, is truly touching. The voyage to New South Wales does not receive remarkably more attention than other aspects of his sailing life. But the love he found reverberates through the decisions he made for many subsequent years. John eventually settled back in Edinburgh when he felt too old to continue his trade at sea, and married a cousin, Margaret. I did find an index entry for this marriage:
Much like Nagle, Nicol struggled to London to try and achieve a pension for himself based on his military service, but to no avail.
John did not have children in his marriage, and Margaret was dead by the time he published his autobiography. John Nicol died in 1824, apparently found dead in his bed.
Apart from the 1824 edition (available in digital form on-line), the story was republished in 1936 (the version I read), and was again reprinted with a new introduction in 1999. The latter is very affordable.