THE BRITISH NATURALIST. 



[February 



after use are hoisted up to the top of the gully. Either gully is used accord- 

 ing to the direction of the wind and the force of the tide, which runs past the 

 Skerry at the rate of six miles an hour. There is one thing I could never 

 account for, and that was the very heavy swells which suddenly got up 

 without any apparent cause. There were 18 men altogether, and they 

 were housed in the hut nearest the lighthouse in one large room, the beds 

 being one above another, like the berths on board ship. I myself had a 

 bed made on the floor in the contractor's hut. I would just like to 

 mention that the " forky tails," more commonly known to us as 

 ear-wigs, were a great pest. I shall never forget my experience of them. 

 I was forced to sleep in all my underclothes, and wrap myself well up in 

 the blankets ; yet they found their way through and bit me badly. The 

 lighthouse is placed almost in the centre of the island, and at its 

 highest point it will be 60 feet high to the lantern ; to a height 

 of 12 feet it is of concrete, 4 feet 9 inches thick, and then of a fire- 

 brick, tapering at the top to 3 feet 9 inches thick. Three men will 

 always be at the lighthouse and one ashore at Stromness, where they 

 have built houses for them and their families. A new steam tender will 

 also be stationed there, for the purpose of changing one man every week, 

 so that each man will be three weeks on the Skerry and one 

 week ashore. It is certain that in the winter months they will never be 

 able to approach the Skerry, possibly for weeks together. One morning 

 I counted nineteen great grey seals on a rock. They seem in no wise 

 disturbed by strangers invading their domain ; possibly they may have 

 taken them for the Crofters' Commissioners, as the members of the 

 "Phocidae" have their little grievances as well as the crofter. In 

 October they come to breed in great numbers, and I believe they climb 

 on to the top into the few shallow, brackish pools of water. How they 

 find their way up is a mystery to me, as it is practically impossible for 

 anyone to find his way down to the water edge. One year upwards of i5o 

 were clubbed by a party of men from Lock Eribol, mainly to procure 

 oil from them for their lamps, the skin being almost worthless. Of course 

 sea birds of every description were there, but I will only speak of those 

 species whose eggs I obtained and have brought for inspection. We 

 will therefore begin with the — 



Great Black-backed Gull {Larus marinus), which is the largest 

 species of the Gull tribe, and measures sometimes 30 inches in length and 

 5 feet 9 inches from tip to tip of wings. They are unsociable birds, even 

 in the breeding season, and build their nests on the most inaccessible 

 rocks. They are exceedingly wary, and soon give notice of the approach 

 of any danger. One of these birds kept one of the men imprisoned for 

 upwards of two hours behind a rock before he was discovered, he being 

 unable to come out owing to it darting at his head. 



Lesser Black-backed Gull {Larus fuscus). — The next in size, like 



