They are to be found in a beautifully written and richly bound manuscript in the Admiralty Library.

At the end of the volume, following the Instructions, are diagrammatic representations of certain actions in the Third Dutch War, finely executed in water-colour to illustrate the formation for attack, and to every plan are appended tactical notes relating to the actions represented, and to others which were fought in the same way.

The first one dealt with is the 'St.James's Fight,' fought on July 25, 1666, and the dates in the tactical notes, as well as in the 'Observations' appended to the articles, range as far as the last action fought in 1673.

The whole manuscript is clearly intended as a commentary on the latest form of the duke's orders, and it may safely be taken as an expression of some tactician's view of the lessons that were to be drawn from his experience of the Dutch Wars.
As to the authorship, the princely form in which the manuscript has been preserved might suggest they were James's own meditations after the war; but the tone of the 'Observations,' and the curious revival of the word 'general' for 'commander-in-chief,' are enough to negative such an attribution.

Other indications that exist would point to George Legge, Lord Dartmouth.