Having no male issue, Sir Humphry, with the design that his daughter and her husband should succeed him in his whole estate and honours, in 1704 resigned his baronetcy into the hands of her majesty Queen Anne, for a new patent to himself in liferent, and his son-in-law and his heirs therein named in fee, but with this express limitation that he and his heirs so succeeding to that estate and title should be obliged to bear the name and arms of Colquhoun of Luss, &c. It was also specially provided that the estates of Grant and Luss should not be conjoined.
Sir Humphry died in 1718, and was succeeded in his estate and honours by James Grant, his son-in-law, under the name and designation of Sir James Colquhoun of Luss. He enjoyed that estate and title till the death of his elder brother, Brigadier Alexander Grant, in 1719, when, succeeding to the estate of Grant, he relinquished the name and title of Colquhoun of Luss, and resumed his own, retaining the baronetcy, it being by the last patent vested in his person. He died in 1747.
By the said Anne, his wife, he had a numerous family. His eldest son, Humphry Colquhoun, subsequently Humphry Grant of Grant, died unmarried in 1732. The second son, Ludovick, became Sir Ludovick Grant of Grant, baronet, while the fourth son James succeeded as Sir James Colquhoun of Luss, the third son having died in infancy. He is the amiable and very polite gentleman described by Smollett in his novel of Humphry Clinker, under the name of “Sir George Colquhoun, a colonel in the Dutch service.” He married Lady Helen Sutherland, daughter of William Lord Strathnaver, son of the Earl of Sutherland, and by her he had three sons and five daughters. In 1777 he founded the town of Helensburgh on the frith of Clyde, and named it after his wife. To put an end to some disputes which had arisen with regard to the destination of the old patent of the Nova Scotia baronetcy, (John Colquhoun of Tillyquhoun, as the eldest cadet, having, on the death of his cousin-german, Sir Humphry Colquhoun, in 1718, assumed the title as heir male of his grandfather, the patentee), Sir James was, in 1786, created a baronet of Great Britain. His second youngest daughter, Margaret, married William Baillie, a lord of session, under the title of Lord Polkemmet, and was the mother of Sir William Baillie, baronet. Sir James died in November 1786.
His eldest son, Sir James Colquhoun, second baronet under the new patent, sheriff-depute of Dumbartonshire, was one of the principal clerks of session. By his wife, Mary, daughter and co-heir of James Falconer, Esq. of Monktown, he had seven sons and four daughters. He died in 1805. His eldest son, Sir James, third baronet, was for some time M.P. for Dumbartonshire. He married, on 13th June 1799, his cousin Janet, daughter of Sir John Sinclair, baronet, and had three sons and two daughters. Of this lady, who died October 21, 1846, and who was distinguished for her piety and benevolence, a memoir exists by the late Rev. James Hamilton, D.D., London.
Old Rossdhu Castle, from the Chiefs of the Colquhouns.
“Some time after Sir James’ succession,” says Mr Fraser, to whose book on the Colquhouns we have been much indebted in this account, “significant testimony was given that the ancient feud between his family and that of the Macgregors, which had frequently led to such disastrous results to both, had given place to feelings of hearty goodwill and friendship. On an invitation from Sir James and Lady Colquhoun, Sir John Murray Macgregor and Lady Macgregor came on a visit to Rossdhu. The two baronets visited Glenfruin. They were accompanied by Lady Colquhoun and Misses Helen and Catherine Colquhoun. After the battlefield had been carefully inspected by the descendants of the combatants, Sir J. M. Macgregor insisted on shaking hands with Sir James Colquhoun and the whole party on the spot where it was supposed that the battle had been hottest. On the occasion of the same visit to Rossdhu, the party ascended Ben Lomond, which dominates so grandly over Loch Lomond. On the summit of this lofty mountain, Sir John M. Macgregor danced a Highland reel with Miss Catherine Colquhoun, afterwards Mrs Millar of Earnoch. Sir John was then fully eighty years of age.”
His eldest son, Sir James Colquhoun, the fourth baronet of the new creation, and the eighth of the old patent, succeeded on his father’s death, 3d Feb. 1836; chief of the Colquhouns of Luss; Lord-lieutenant of Dumbartonshire, and M.P. for that county from 1837 to 1841. He married in June 1843, Jane, daughter of Sir Robert Abercromby of Birkenbog. She died 3d May 1844, leaving one son, James, born in 1844.
The family mansion, Rossdhu, is situated on a beautiful peninsula. To the possessions of the family of Colquhoun was added in 1852 the estate of Ardincaple, purchased from the Duchess Dowager of Argyll. According to Mr Fraser, the three baronets of Luss, before Sir James, purchased up no less than fourteen lairdships.