The captain had to record his survey in painstaking paperwork, and Darwin too kept a daily log as well as detailed notebooks of his finds and speculations, and a diary which became his journal. Darwin's notebooks show complete professionalism that he had probably learnt at the University of Edinburgh when making natural history notes while exploring the shores of the Firth of Forth with his brother Erasmus in 1826 and studying marine invertebrates with Robert Edmund Grant for a few months in 1827. Darwin had also collected beetles at Cambridge, but he was a novice in all other areas of natural history. During the voyage, Darwin investigated small invertebrates while collecting specimens of other creatures for experts to examine and describe once "Beagle" had returned to England. More than half of his carefully organised zoology notes deal with marine invertebrates. The notes also record closely reasoned interpretations of what he found about their complex internal anatomy while dissecting specimens under his microscope and small experiments on their response to stimulation. His onshore observations included intense, analytical comments on possible reasons for the behaviour, distribution, and relation to their environment of the creatures he saw. He made good use of the ship's excellent library of books on natural history but continually questioned their correctness.