It had become instantly clear, however, that the original provision of eighty-two trawlers would be insufficient; and, by the end of August, this had been increased to 250--to be yet further and immensely added to as the busy months went by. Nothing in our naval record, indeed, was more dramatic or so signal an evidence of the national sense of admiralty than the gathering together of that vast auxiliary service of fishermen, pilots, and amateur yachtsmen, and the enormous responsibilities thrust into their hands to be so efficiently and light-heartedly carried. Time after time, by the resource of our fishermen, of sea-loving undergraduates, of amateurs of all sorts, what might have been disasters of the first magnitude were averted or overcome. Between the navy proper, with its thousands of other problems, and these new and insidious dangers--the laying of minefields by apparently innocent neutrals, the ever-present activities of enemy submarines--the courage, the cunning, the native sea-instinct of these otherwise untrained forces was the buffer. The fishermen of Galilee became fishers of men. The fishermen of Britain became fishers of mines. And the debt of human freedom to the latter is not immeasurably less, perhaps, than to their predecessors. {87} This was the true picture then of the North Sea--an area nearly three times the size of Great Britain--a Grand Fleet holding the exits and entrances against every possible sortie in force, but itself so threatened by submarines and minefields that at one time its war-stations were actually changed, and so nearly paralyzed that there were not a few hours when considerable units of it were practically embayed. Thus, definite minefields were laid by the enemy at Southwold, the mouth of the Tyne, and near Flamborough Head, and not only there but off the north of Ireland, where it was hoped to destroy or disorganize the Canadian transports. Nor were our most vital waters, such as those of the Firth of Forth, free from the repeated visits of those early submarines; and it is primarily as trapping expeditions, leading us into prepared minefields, and only secondarily as baby-killing bombardments, that such raids as those on Lowestoft, Gorleston, and Yarmouth must in reality be considered.