“Wait off the Briggs till the light was seen, then stood in upon the Briggs till the light was shut in by the land of Cairnbulg, and at that moment had 8 fathoms water, so that at present the light forms an excellent direction for Rattray Briggs.
“Find that the lightroom is seen fully from the yacht’s deck in 8 fathoms water off Rattray Briggs, that the flag upon the masthead is seen in 6 fathoms water--high water spring tides. Ship then bearing from the head E.S.E. and W.N.W., distant about one mile from the shore, where a man is distinctly observed at a boat in the twilight.
“_Secondly._--Remove the mast from the castle or lighthouse on the morning of the 15th to Cairnbulg, and elevate a flag to the height of 86 feet from the ground, or 97 feet from high water mark, at the distance of about 100 yards from the high water mark at the point connected with Cairnbulg Briggs.
“The yacht lying off or to the westward of the Briggs, was got under weigh at 2 A.M. of the 16th, and beat up the north shore as far as Rosehearty, and there observed the flag over the land. Found off Rosehearty that the flag was just hid by the highest inequalities of the land to the southward of the Castle, and that it appeared at the lower or flat places sometimes in sight 20 feet above the land, and at other places intercepted by the land and houses of the town, amongst which it often appeared and disappeared. The range of the flag along the land was as far as Mr. Dalrymple’s house when it was time to put about, having there three fathoms at nearly low water.
“After completing the observations in this direction, sailed along the shore southwards to Rattray Briggs. Find that Inverallochy head, south-eastward of the town of Cairnbulg, is the eastmost point on this coast, but, being at a distance from the foul ground of Cairnbulg, would make a less desirable point than Cairnbulg.
“Off Rattray, in eight fathoms water, begin to lose sight of the lantern on Kinnairdhead Castle as before. See the mast and flag at Cairnbulg a considerable way up the country over the lands of Inverallochy. See the flag, standing in upon Rattray to five fathoms water at half tide, lose it, and then stand for Fraserburgh.
“As the result of these trials, find that Inverallochy head or point is the most eastern or projecting point of land upon that coast, that Cairnbulg is the next projecting point. The former lies between the points of danger, viz., Rattray and Cairnbulg.