With a bundle which consisted of his rubber boots, a worn suit of overalls, and with his pick and shovel over his shoulder, he followed. He reached the bottom of the pit, boarded as to the sides with huge oak planks sustained by cross beams, and there, with several others who were waiting until the air pressure should be adjusted, entered the lock. The comparatively small and yet massive chamber, with its heavy iron door at either end, responding so slowly to pressure, impressed him. There was only a flickering light made by a gasoline torch here. There was a whistling sound from somewhere. “Ever work under air pressure before, Paddy?” inquired a great hulking ironworker, surveying him with a genial leer. “Air what?” asked McGlathery without the slightest comprehension of what was meant, but not to be outdone by mere words. “No, I never did.” “Well, ye’re under it now, two thousand pounds to the square inch. Don’t ye feel it?” Dennis, who had been feeling an odd sensation about his ear-drums and throat, but had no knowledge that it was related to this, acknowledged that he did. “’Tis air, is it?” he inquired. “’Tis a quare feeling I have.” The hissing ceased. “Yuh want to look out fer that, new man,” volunteered another, a skimpy, slithery, genial American. “Don’t let ’em rush that stuff on yuh too fast. Yuh may git the ‘bends.’” Dennis, ignorant as to the meaning of “bends,” made no reply. “D’yuh know what the ‘bends’ is, new man?” persisted the other provocatively. “Naw,” replied Dennis awkwardly after a time, feeling himself the centre of a fire of curious observations and solicitation. “Well, yuh will if yuh ever git ’em—haw! haw!” this from a waggish lout, a bricklayer who had previously not spoken. The group in the lock was large. “It comes from them lettin’ the pressure be put on or took off too fast. It twists yer muscles all up, an’ does sumpin’ to yer nerves. Yuh’ll know it if yuh ever git it.” “Member Eddie Slawder?” called another gaily. “He died of it over here in Bellevue, after they started the Fourteenth Street end. Gee, yuh oughta heerd him holler! I went over to see him.”