Did Karl Marx Write About The Infamous Dutchess Of Sutherland And The Highland Clearances?

Yes he did - in the The People's Paper, No. 45, March 12 1853;
She had said of the Scottish tenants on her estates -in  a letter to a friend in England;

"Scotch people are of happier constitution, and do not fatten like the larger breed of animals."

Marx wrote  about the family , the extract below appeared in 1853.
'The history of the wealth of the Sutherland family is the history of the ruin and of the expropriation of the Scotch-Gaelic population from its native soil. As far back as the 10th century, the Danes had landed in Scotland, conquered the plains of Caithness, and driven back the aborigines into the mountains. Mhoir-Fhear-Chattaibh, as he was called in Gaelic, or the "Great Man of Sutherland", had always found his companions-in-arms ready to defend him at risk of their lives against all his enemies, Danes or Scots, foreigners or natives. After the revolution which drove the Stuarts from Britain, private feuds among the petty chieftains of Scotland became less and less frequent, and the British Kings, in order to keep up at least a semblance of dominion in these remote districts, encouraged the levying of family regiments among the chieftains, a system by which these lairds were enabled to combine modern military establishments with the ancient clan system in such a manner as to support one by the other.