Sentence:  ... through their whole controversy with the Court of Directors, they do not so much as hint at their ever having seen any other paper from lord Macartney, or any other estimate of revenue, than this of 1781. To this they hold. Here they <WSD>take post</WSD>; here they entrench themselves. 
Meaning of the word marked with <WSD> tags:  To arrive in and occupy a position (somewhere), often a military one; to establish or station oneself in a (defensive or offensive) position.