42 THE SALMON FISHERIES. 
produce of the fish-lock at Bywell itself increased, and the 
salmon harvest of the Tyne generally improved. In 1862 
a flood carried away part of the dam, with the immediate 
result that the take of fish in the river above again largely 
increased. The owner of the weir, the late Mr. Beaumont, 
having abstained from reconstructing the weir, the fish 
have since had uninterrupted access to several miles of 
spawning ground above the site of the dam ; the fisheries 
above have so largely improved in value that the proprietors 
have been induced to take further steps to encourage the 
salmon by removing other obstacles to their ascent, and, 
although the Tyne is still seriously handicapped by the 
existence of weirs in its upper waters, and by terrible 
pollutions near its mouth, its salmon fisheries, which would 
in all probability have gone the way of those of the 
Thames, if Bywell dam had remained unremedied, are 
now more productive than those of any river in England 
and Wales, producing about 50,000 salmon a year. 
A similar lesson may be learned on the Usk. A salmon 
river of splendid natural capabilities, its productiveness was 
for many years seriously affected by a formidable fishing- 
mill-dam at Trostrey, about seven miles above the head of 
the tideway. Except at time of heavy floods, this weir was 
impassable by salmon. To its existence the decrease in 
the fisheries of the Usk, which began to attract attention 
sixty years ago, was attributed. How far this was the 
case may be gathered from the fact that, the weir having 
been carried away by a flood in the winter of 1823-24, the 
catch of salmon in the fishery above was larger in the 
spring of 1824 than had ever been known before. Con- 
nected with the weir were three fishing boxes or traps, for 
which the occupiers paid a rent of £100 a year, and which 
were said to be worth five times as much. On the other 
