In their own words

On the 17th Blake commenced his charting of the island. Hamilton was kept busy with marine collecting and securing specimens of the varied bird life.

Hamilton’s biological work had a special interest, for it was to have a very important bearing on a theory widely supported, namely, that the continental land masses of the Southern Hemisphere were, at one period or another, all joined together. This theory had been advanced to explain the anomalies in the distribution of plant and animal life. Our own immediate interest in the problem lay in the suggested connection of Australia with South America through Antarctica. Perhaps a study of the fauna and flora would reveal that Macquarie Island was an unsubmerged relic of a former land bridge connecting these places, So it was evident that our scientific opportunities were unique.

— George Ainsworth’s report in The Home of the Blizzard