This weblog is going to be the transcription of ABEL TASMAN's Journal of his voyage of discovery 1642-1643, as translated into English from the old Dutch by Brian Hooker.
Here I shall attempt to give life to the document by adding my own data and commentary. All other comments are welcome.
JOURNAL or description drawn by me, Abel Janszoon Tasman, of a voyage made from the town of Batavia in the East Indies, relating to the discovery of the unknown southland in the year of our Lord 1642, the 14th of August. May it please God almightly to give hereto His Blessing on this work. Amen.
14 August 
Sailed from the roadstead at Batavia with two ships, to wit: the yacht Heemskerck [pronounce Hems-kirk] and the flute Zeehaen [Zay-han]. In the evening the Zeehaen grounded on the island of Rotterdam [in the area of Jakarta] but got afloat again without notable damage. Then we continued on the voyage heading for Sunda Strait [between Sumatra and Java, 16 ks wide].
That's all for 14 August 1642... What he forgot to say is the explosion of Dutch swearing that the Heemskerck's crew uttered when they saw the Zeehaen get grounded. I don't know how you spell it but it is the equivalent of f... h..., phonetically more spicy.
I pass the entry for the 15th.
At our anchorage the wind was northeast and we noticed a strong current flowing through Sunda Strait. In the evening, with the land breeze we raised our anchors and shaped our course so as to pass between the Prince Islands and Krakatau.
What you need to know here is that Batavia (Jakarta) is situated in the southern tropical zone, on the Tropic of Capricorn. The prevailing wind is what you call the southern trade wind and it usually blows from the south-east. In any case it blows from the east.
Captain Tasman in fact takes the rhumb line to sail back to Holland, and as far as Mauritius island he expects to have fair winds pushing him. What you need to understand about the land breeze and raising anchors, is that at sea on a sail boat anyway you are always waiting on nature. A good skipper does not 'decide' to raise anchor at 3 pm sharp or at 9.24 am like a train. He waits for the exact moment when nature allows him. A land breeze is going to push the ships towards high sea, the maximum highly dreaded danger being to get pushed towards the land, especially if there is some current.