300 THE SALMON RIVERS OF SCOTLAND 



ence to prevent fish running up too fast and being lost in the large 

 loch. The formation of the dyke on the lowest loch carries a tale 

 with it, which will be given presently. At other lochs in the Lewis 

 the dams have now been allowed to fall into disrepair and useless- 

 ness. 



A peculiar affection sometimes is noticeable amongst the fish 

 which lie long in the shallow salt-water bays waiting till suitable 

 floods come for their ascent. It is locally described as the White 

 Spot, and has no connection with the ordinary salmon disease. 



Through the kindness of Mr. George Pople, the present tenant 

 of the Grimersta fishings, I have received several specimens 

 of fish showing this peculiar ailment. When the streams 

 become sufficiently swollen after rain to admit of their ascent in 

 fresh water, "the white spot" disappears. The only reference to 

 this disease of which I am aware is in Scottish Moors and Indian 

 Jungles, p. 141, by Captain J. T. Newall, who was at one time tenant 

 of Scaliscro shootings, just south of Grimersta. It is as follows ; 

 "The summer in the Lews in 1880 was remarkable for the unusual 

 heat. Salmon, in consequence, could not ascend the rivers, which 

 became so attenuated as to afford no waterway for them. Fresh 

 water being equally necessary as sea for the health of the fish at the 

 proper season, they suffered in consequence. Many became quite 

 blind, and developed a white spot on the head, the result being the 

 death of numbers near the mouths of rivers." The natural inference 

 is that the lack of fresh water is responsible for this trouble. This 

 I consider very unlikely indeed. The blindness, the bright sunshine 

 of hot weather, the perfect translucency of the sea water around 

 these western islands, and the shallow nature of the estuaries or 

 bays in which the fish congregate, seem to me to suggest a different 

 cause. One is reminded of the pale-skinned, sightless condition to 

 which fish are reduced when confined too long in aquaria exposed to 

 sunlight. When in Stornoway in 1902, 1 was informed by a former 

 gamekeeper at Stornoway Castle, the present lessee of the Royal 

 Hotel, that in summers when this disease is really bad, the fish 

 become so helpless that boys stone them and drag them ashore in 

 the neighbourhood of the harbour, but it is evidently unusual for 

 fish to become blind or to die of the disease. Mr. Pople, in sending 

 me the specimens referred to, informs me that he had never seen a 

 fish dead from this cause. The summer of 1905 was unusually dry, 

 and one of the specimens sent was described as the worst Mr. Pople 

 had seen during his tenancy. The dull white appearance had 



