George married after the age of fifty but died four months later, wife's name not known (Catherine Dunscomb Colt notes). As of 1844 he was one of the principle shareholders of the Newfoundland Bank which was incorporated on that date (Don Morris, St. John's Newfoundland Dept of Tourism letter 4/4/1977).
George was educated in England (Dartmouth, Devonshire 1829-1834 and returned to his father's business in St. John's. He eventually founded Dunscomb & Harvey with Eugenius Harvey of Bermuda, then moved to New York with Harvey taking over the company in St. John's (Matthews, Keith. Profiles of Water Street Merchants, 1980. Memorial University of Newfoundland).
George's wife was considerably youger than he. Following his death in Florida she returned to Canada where her child was born (Catherine Dunscomb Colt notes).
St. Margaret's Episcopal Church Cemetery, Fleming Island, Clay County, Fliorida has a grave marked
"George H. Dunscombe, wooden cross, no dates." (http://searches1.rootsweb.com/usgenweb/archives/fl/clay/cemetery/stmargarets.txt)
In 1840, when his father dissolved the partnership with Michael Kavanagh, he (he being George (editor) went separately into business with Kavanagh. On the death of Kavanagh in 1841, George Dunscombe entered a new partnership with Eugenius Harvey of Bermuda as Dunscombe and Harvey (by now his father was nearing retirement). George Dunscombe moved to New York whilst Harvey managed the business in St. John's (on behalf of John Dunscombe, senior). This partnership was dissolved in 1847. Harvey inherited the business of Dunscombe and Company in St. John's whilst George Dunscombe went his own way in the United States... (Profiles of Water Street Merchants, by Keith Matthews, Maritime History Group, 1980 (possibly on file at Memorial University of Newfoundland).

The following is an excerpt from a letter by family researcher Henry M. West Winter to Bermudian genealogist William Zuill dated March 23, 1936. The full text can be read at the profile of John Dunscombe (1777-1847). This section relates to George:

"The seventh child was George Hoyles Dunscomb, a banker of Cobourg, Ontario, who died in Florida in 1871 leaving a posthumous son, Geeorge Hoyles Dunscomb Jr., until recently the President of a Bank in Chicago."

From "Some recollections" by Cyprian Bridge (1918):

" My maternal grandfather had a large family, my mother being the youngest of four daughters. The youngest son, George, whom I remember, was one of my godfathers. I have always thought him the handsomest man I ever saw. He was over six feet in height and of a well-proportioned and upright figure. He was an extraordinarily enthusiastic fisherman, for many years of his life spending most of his time with a fishing-rod in his hand. There was no distance, which he thought too great, of covering it would give him a prospect of good fishing. He once told me that he had walked in North-western America five hundred miles in company with some Indians, and five hundred miles back, all for the sake of fishing at a particular place, where, however, the sport proved disappointing. He was probably one of the first Englishmen to go regularly to Norway to fish, as he went there over seventy years ago.
As my godfather, he was always very nice to me; but the only thing he ever gave me was a fishing rod of very excellent quality, which I used for years. The gift was handed to me shortly after his return from a fishing expedition to Norway, just as we were on the point of leaving Paddington terminus for a journey by the Great Western Railway. The difficulties of keeping it without injury in a railway carriage of those days were great enough to make me remember the circumstances."