Original: Gilbert then sailed for Sydney, in the middle of June 1840 took ship to Port Essington in the north of Australia, and in March 1841 sailed to Singapore calling at Timor on the way.
Simplified: Gilbert then sailed for Sydney, and in June 1840 took a ship to Port Essington in the north of Australia. In March 1841 he sailed to Singapore, stopping at Timor on the way.