Another very rare visitor seen here this month was a sheldrake, which passed close overhead flying south. This is the first I have seen here, but in Orkney these birds are very numerous and are there known as the burrow duck, or sly-goose. Sly they certainly are, as evidenced by a pair which nested regularly within a couple of hundred yards of the lighthouse at which I was then stationed. A covered drain was the site annually chosen, the nest being placed several yards from the mouth, which opened out on a spacious grassy hollow. The bright brown and white plumage, with vermilion bill and feet, render these birds most conspicuous objects in an ordinary landscape; but squatting on a shingly beach, where their colours harmonise better with their surroundings, their presence is less easily detected. Frequently I have watched their movements with a telescope from the lantern, and though no one was stirring within seeing distance of them, the greatest caution was always exercised in approaching the nest. Lighting a hundred yards from the nest, a pretence of feeding diligently was made, though their heads could be seen frequently lifting in the direction from which intrusion was to be expected. Gradually circling nearer the nest, passing and repassing it with apparent indifference, till within a few feet of it they would then suddenly vanish. The exact moment of their entrance I was never able to note, as they appeared to assume an invisibility during the remaining few feet of their journey that was really astonishing, but which is less a matter of surprise when one has witnessed the squatting in concealment of a hen pheasant on sparse grassy ground. Burrow duck is a name applied to these birds from their habit of nesting in disused rabbit burrows. I have counted as many as forty young ones following a single pair, while others may have only three or four juveniles in their train. It is said they do not scruple to steal the young ones from each other. If alarmed while feeding among the decaying seaware on the beach, some of the parents will fly to meet the intruder and endeavour to divert his attention in another direction, while the others fly seawards, followed by their callow broods flapping their little wings, while their feet tip-tip the surface--a veritable walking on the waters.