METHODS OF FISHING
	to breathe while at work, it also entails dangers and difficulties from which the old method is free. An imperfect supply of air may cause the bursting of a blood-vessel. Fouling of the lines might not only cut off the air supply entirely, but prevent the man, anchored by his heavy dress under twenty fathoms of water more or less, from signalling the man at the life-line. As on dry land, there are holes and precipices at the bottom of the sea to be avoided. In some seas there are swift currents and as the dress-diver remains under water for some time, instead of returning at once like his naked brother, he must keep moving with it, and as he moves, the boat must move in unison and his tender must keep the lines free. Both diver and tender must be skilful and alert to do this. Nor is it always easy in deep-sea diving to find the oysters. They lie in scattered bunches, often hidden by sponges, coral or other sea growths, their gray or moss-grown exteriors scarcely to be distinguished from the surround­ings ; if in mud, only an inch or so of the sharp lips of the two valves projecting above the surface are in evidence; while if in stooping to 13                                  193