Complex sentence: Haldane was afterwards present at the relief of Gibraltar, but at the peace of 1783 he finally left the Royal Navy, and soon afterwards settled on his estate of Airthrey, near Stirling.
Split into simpler sentences: Haldane was afterwards present at the relief of Gibraltar, but after the peace of 1783 he left the Royal Navy. Soon afterward leaving the Navy, he settled on his estate of Airthrey, near Stirling.