The capture of a 4-lb. grilse in the Thames estuary in December, 1901, raised some hopes that we might in course of time see salmon at London Bridge. Mr. R. Marston, a great authority, in an article on "The Thames a Salmon River," in the Nineteenth Century, has given many reasons why he fears that this will not be realised. The question is not so much whether the salmon can come up, as whether the smolts, or young salmon, could get down through the polluted water. But the experiments made are interesting and deserve every encouragement, and it may be hoped that money will be forthcoming to make more.

As regards other fish than salmon, their return has been going on steadily since 1890; and their advance has covered a distance of some twenty miles - from Gravesend to Teddington. The first evidence was the reappearance of whitebait, small crabs, and jelly-fish at Gravesend in 1892. In 1893 the whitebait fishermen and shrimp-boats were busy ten miles higher than they had been seen at work for many years. The condenser tubes of torpedo-boats running their trials down the river were found to be choked with "bait," and buckets of the fish were shown at the offices of the London County Council in Spring Gardens. It was claimed that this evidence of the increased purity of the water was mainly due to the efforts of the Main Drainage Committee of the London County Council. There is abundant evidence that this claim was correct, for instead of allowing the whole of the London sewage to fall into the Thames at Barking and Crossness, the County Council used a process to separate all the solid matter, and carried it out to sea. The results of the first year's efforts were that over two million tons were shipped beyond the Nore, ten thousand tons of floating refuse were cleared away, and the liquid effluent was largely purified. It was predicted at the time that if this process was continued on the same scale it would not be long before the commoner estuary fishes appeared above London Bridge, even if the migratory salmon and sea-trout still held aloof. Unfortunately there has been some deviation from the methods of dealing with the sewage, a change from which we believe that some of the officials concerned with the early improvements very strongly dissented, that has to some extent retarded the advance of the fish. But in 1895 a sudden "spurt" took place in their return. Whitebait became so plentiful that during the whole of the winter and spring the results were obvious, not only to naturalists, but on the London market. Whitebait shoals swarmed in the Lower Thames and the Medway, and became a cheap luxury even in February and March. They were even so suicidally reckless as to appear off Greenwich. Supplies of fresh fish came into the market twice daily, and were sold retail at sixpence per quart. The Thames flounders once more reappeared off their old haunt at the head of the Bishop of London's fishery near Chiswick Eyot. Only one good catch was made, and none have been taken since; but this had not been done for twelve years, and there is a prospect of their increase, for, in the words of old Robert Binnell, Water Bailiff of the City of London in 1757, we may "venture to affirm that there is no river in all Europe that is a better nourisher of its fish, and a more speedy breeder, particularly of the flounder, than is the Thames." Eels were also taken in considerable numbers between Hammersmith and Kew; but the main supply of London eels came from Holland even in the days of London salmon. In a very old print of the City, with traitors' heads by the dozen on London Bridge, "Eale Schippes," exactly like the Dutch boats lying at this moment off Billingsgate, are shown anchored in the river. Besides the estuary fish which naturally come up river, dace and roach began to come down into the tideway, and during the whole summer the lively little bleak swarmed round Chiswick Eyot. Later in the year the roach and dace were seen off Westminster, and several were caught below London Bridge, and in 1900 roach were seen and caught at Woolwich, but were soon poisoned and died. In August the delicate smelts suddenly reappeared at Putney, where they had not been seen in any number for many years. Later, in September, another migration of smelts passed right up the river. Many were caught at Isleworth and Kew, and finally they penetrated to the limit of the tideway at Teddington, and good baskets were made at Teddington Lock.

This additional evidence of the satisfaction of the fish with the County Council does not quite satisfy us that the London river is yet clean enough to give passage to the migratory salmon. It is encouraging to the County Council, who deserve all the credit they can get; but there is little doubt that the best evidence that the river is fit for the salmon would be the spontaneous appearance of the salmon themselves.