The chief danger of caisson work is the “bends,” or “caisson disease.”  In the caisson a man works under high air pressure.  When he comes out, the pressure on the fluids of the body is reduced, and this sometimes causes the formation of a gas bubble in the vascular system.  If this bubble reaches a nerve-center it causes severe pain, similar to neuralgia; if it gets to the brain it causes paralysis.  Day after day men will go into the caisson and come out without trouble, but sooner or later from 2 to 8 per cent. of caisson workers are affected.  Of 320 “sand-hogs” who labored in the caissons of this bridge, three died of paralysis, and of course a number of others had slight attacks of the “bends,” in one form or another.

The bridge, when we visited it, was more than half completed.  On the Memphis side the approaches were almost ready, and the steel framework of the bridge reached from the shore across the front pier, and was being built out far beyond the pier, on the cantilever principle, hanging in the air above the middle of the stream.  By walking out on the old bridge we could survey the extreme end of the new one, which was being extended farther and farther, daily, by the addition of new steel sections.  There were then about 100 journeymen bridgemen on the work—­these being workmen of the class that erects steel skyscraper frames—­with some fifty apprentices and carpenters, and about twenty common laborers.  Bridgemen are among the highest paid of all workmen.  In New York, at that time, their wage was $6 for eight hours’ work.  Here it was $4.50.  Very few of the men had families with them in Memphis.  They are the soldiers of fortune among wage-earners, a wild, reckless, fine looking lot of fellows, with good complexions like those of men in training, and eyes like the eyes of aviators.  No class of men in the world, I suppose, have steadier nerves, think quicker, or react more rapidly from stimulus to action, whether through sight or sound.  They have to be like that.  For where other workmen pay for a mistake by loss of a job, these men pay with life.  Yet they will tell you that their work is not dangerous.  It is “just as safe as any other kind of job”—­that, although four of their number had already been lost from this bridge alone.  One went off the end of the structure with a derrick, the boom of which he lowered before the anchor-bolts had been placed.  Two others fell.  A fourth was struck by a falling timber.

Once, while we were watching the men scrambling about upon the steel members of the uncompleted cantilever arm, one of them thought something was about to fall, and ran swiftly in, over a steel beam, toward the body of the structure; whereafter, as nothing did fall, he was unmercifully twitted by his fellow workers for having shown timidity.