26 THE SALMON RIVERS OF SCOTLAND 



course of about 38 miles. The last two miles are in England, for 

 the Tweed before the junction is reached has passed wholly out of 

 Scotland. The line of the Whitadder, and its erosion of the old 

 land surface, forms a natural passage from the Borders towards 

 Edinburgh, and a chain of castles formerly guarded this line as 

 similar structures already referred to kept watch over Tweedside. 

 The river does not become of any great size till Abbey St. Bathans 

 is reached, a former Cistercian settlement now no longer in existence. 

 The county is typical of Berwickshire, with its undulating stretches 

 of highly farmed land interspersed with woods and fertile meadows. 

 Cockburn's Law, close to the river is a well-marked feature and is 

 interesting to geologists as a granite cone resting on the greywacke 

 of the surrounding country. 



At Chirnside the Whitadder is joined by the Blackadder, another 

 stream of considerable length some 16 miles wholly in Berwick- 

 shire. It rises in the parish of Westruther on the southern slopes 

 of the Lammermoors, which divide the head streams from Lauderdale. 

 It flows east by Greenlaw in a direction almost parallel to Tweed, 

 and thus joining the south-coming Whitadder at a fully abrupt 

 angle. Sir Thomas Dick Lauder, 1 speaking of Westruther parish, 

 quotes an interesting passage from the Statistical Account which in 

 explaining that the name was originally Wolfstruther, or Wolf's 

 Swamp, speaks of it " as a place of old which had great woods, with 

 wild beasts, fra quhilk the dwellings and hills were designed as 

 Wolfstruther, Roecleugh, Hindside, Hartlaw, and Harelaw." 



There are nine weirs on the Whitadder and two on the Blackadder, 

 but none of them need be regarded as very serious obstacles to 

 ascending fish, in spite of the fact that only one, at Chirnside, has a 

 pass. The paper works at Chirnside are provided with nine settling 

 tanks and a filter of ashes, so that a great part of the deleterious 

 matter is kept from the effluent. At Cumledge, on the river above 

 Chirnside, the woollen mills have also tanks, where the effluent is 

 treated with sulphuric acid and neutralised. At Greenlaw, on the 

 Blackadder, chemical refuse from dyeing and scouring wool was run 

 into the river untreated before the local mill was burnt down. 

 Greenlaw is a long way upstream, however, and the water is small. 



The Whitadder is the great tributary for sea- trout, and at times 

 large numbers of these fish ascend. The sea-trout of the Tweed is 

 now almost exclusively the bull-trout or round- tail 8. trutta var. 

 eriox, the same fish as ascends the Coquet. It is a bad rising fish, 



1 Scottish Rivers, 1890, p. 254. 



