what were the terms decided upon between the caption and gulliver for the voyage on hopewell?

From the text:

Gulliver reports that the Captain assured him of the following terms;

"that I should have another surgeon under me, beside our two mates; that my salary should be double to the usual pay; and that having experienced my knowledge in sea-affairs to be at least equal to his, he would enter into any engagement to follow my advice, as much as if I had shared in the command."