J.G.C. BLACKHALL, Esq., Caraquet (Glouc. Co.,) has sent the 'Union Advocate' the following account of a sad accident which occurred on the night of 14th inst. - On Monday night Archibald KERR s/o the light house keeper on Caraquet Island and John AHERN s/o Simon AHERN both of New Bandon, left the mainland between 6 and 7 o'clock in the eve. in a flat. On Tuesday, Mr. KERR, father of Archy, found a flat near the Island bottom up which he hauled up in safety; and in the afternoon came across to the main land where he heard that his son and AHERN had left the night before. Search was made yesterday for the bodies but no trace of them was found. Young KERR was a single man. AHERN leaves a wife and 2 or 3 children. This is the fourth son (grown to manhood) that Thomas KERR has lost within a very few years and the second that was drowned. (abridged)