greg - the source given for Lord Inchiquin is the Bunting MSS in Queen's University Library, Belfast. Bunting published his earliest collection in 1796. O'Sullivan says of it: "they are the richest single source not only for Carolan's music but also for his verse...Moreover, the music was obtained from the most authentic sources, namely, the harpers who were Carolan's immediate successors". So no real help with dating there. However his dates are 1670 - 1738, so in 1719 he was still only 48 with another 19 years or so to live, so no reason he shouldn't still be writing (I haven't read far enough to confirm or deny that).

Ian - (since I have been started on this pesky re-reading business) in the chapter called His Subsequent Career after quoting (and denying the validity of) a few statements about Carolan only being at his best for descendents of the Gael, he goes on to say (lengthy quote I'm afraid):

"A survey of either Carolan's tunes of his words can leave us in no doubt as to the position...we can find no distinction in quality between those he composed for 'the descendents of the Gael' and those which were made for their supplanters...
  Was Carolan, then, unpatriotic- or worse still, a renegade and a sycophant? The answer is that he was none of these things, but merely one of a class of Irish harpers and poets who followed a tradition that had been established centuries earlier. We have already seen that the Irish bardic poets of the fifteenth century composed impartially for the old Irish aristocracy and for the noblesof English origin...
  It is to be said, then, that to animadvert on Carolan's failure to discriminate in the choice of patrons and on the absence of the patriotic note in his verse is to judge him by a false standard. Like other poets and harpers of his time, he observed the old-established convention of his profession, a convention which may be justified by the considerations of courtesy, social decency and savoir faire. The great Irish families freely opened their doors to him, and they would hardly have done so if he had violated their sense of propriety in making songs for their supplanters as well as for themselves. In such a case, moreover, he would not have been accorded praise by patriotic poets like MacCuarta and MacAlindon."

Mick