“The surface was evidently very irregular,” he wrote, “composed of alternate projections and depressions, the extreme difference in elevations encountered being 16 feet, and occurring chiefly along the water edge.” Throughout the central section, however, and covering at least two-thirds of the entire area, the irregularities were much less, amounting to maybe no more than three or four feet. As near as he could tell, the caisson was about to settle on a broken ridge of rock running diagonally from one corner of the caisson to the other and having a dip of perhaps five feet in a hundred toward the land, but falling off rapidly toward the east.
Roebling now faced what would be the most difficult decision of his career. He himself was very near to a physical collapse. He had been spending as much time in the caisson as anyone, but going up and down through the locks, to check on this or that below, many times more often than the average laborer. He was on the job constantly, working twelve to fourteen hours a day, six days a week, frequently making three and four trips a day on the ferry, going back and forth from the Brooklyn offices. Most of his time was spent on the site itself. But it was the only way he could have worked. He was not an office engineer and had little regard for those who were.
At this point he could either keep the caisson descending until he had level rock on which to leave it or he could stop about where he was, before reaching rock. To continue deeper would mean enormous expense and time lost blasting the irregular rock ridge down to a comparatively even surface. It might also mean more lives lost. Already Smith had recorded more cases of the bends than Jaminet had in St. Louis. And whereas Eads had not suffered a single fatality until his first caisson was down ninety-four feet and the pressure was at forty-four pounds, Roebling, for some unknown reason, had already lost two men. So at this rate the New York caisson might take even more lives than the thirteen the St. Louis foundations had cost by the time they were in place.
Emily Roebling would remark later that her husband estimated it would take another year to go to bedrock and that it would cost another half a million dollars and possibly a hundred lives.
To leave the tower standing on anything other than bedrock, however, would seem to put the stability of the entire bridge in jeopardy. Yet Roebling, to the surprise of many, was now not so sure about that. The sand and gravel covering the rock was so compact, so very hard, he said, that it might provide as solid a footing as rock itself. Earlier, when they were down sixty feet or so, the men had uncovered the bones of a domestic sheep, and just below that fragments of brick and pottery, indicating that the strata at that level had changed within the time man had been around. But in the last ten feet and more, no such evidence had been unearthed; the strata showed no signs of having been disturbed since the time of deposit several millions of years in the geologic past and so in all likelihood it would remain perfectly stable. As Roebling noted, it was now nearly impossible to drive in an iron rod without battering it to pieces. The material, he would write in his forthcoming report, was “good enough to found upon, or at any rate nearly as good as any concrete that could be put in place of it.”
If he was right about this, then the enormous stone tower could rest there as well as anywhere and his problems would be solved. But if he was wrong, then there was the chance that the tower might begin to lean or slip and the bridge would be a disastrous failure. Possibly, others noted, the tower might even slide into the river.
“The period of time at the end of the sinking of the New York caisson was,” his wife would say, “one of intense anxiety for Colonel Roebling.”
But the decision could wait a little.
At a depth of seventy-five feet the first spur of bedrock, the ordinary gneiss of Manhattan Island, was encountered under the shoe on the river side. “No part of its surface shows the rounding action of water or ice,” Roebling reported. “On the contrary, the outcrop is in the form of sharp thin ridges, with steep vertical sides occurring in parallel ranges.”
On May 17 one man became paralyzed in the legs and arms; another complained of savage pains in his legs; a third, an Englishman named Reardon, began retching violently after coming up from the afternoon shift. In minutes he was seized by excruciating leg cramps and pitched forward, unable to walk or stand. The vomiting continued all night and Dr. Smith had him taken to the Center Street Hospital, where he grew steadily worse. The following morning he died. Smith wrote in his notebook that Reardon had been “corpulent” and that the autopsy showed his spinal cord to be “intensely congested.”
That same day, May 18, 1872, with the caisson at a depth of seventy-eight feet six inches, Roebling ordered that the digging stop. He had decided
not
to go to bedrock, staking his reputation and career on the decision. The New York tower would rest on sand.
The second and last great caisson was therefore in position, and as Collingwood noted, the differences of level at the extreme corners, as measured on the masonry above, was only three-fourths of an inch. It had been a spectacular feat of engineering.
The work of filling the air chamber began at once and Roebling finished his report to the directors. If anyone was upset about the incidence of caisson sickness, Roebling said only that the trouble had not been so serious as he had anticipated. He made no mention of the number of cases there had been and claimed that just two deaths could be charged directly to the effects of pressure. As for the unsung individual suffering there had been, he said only this: “The labor below is always attended with a certain amount of risk to life and health, and those who face it daily are therefore deserving of more than ordinary credit.”
At the end of May, Dr. Smith resigned his position and went back to the Eye and Ear Hospital, satisfied his work was complete, his services no longer needed now that the caisson was at rest. But work inside the caisson continued right along, the concrete for filling it in being mixed above, then let down through the supply shafts. No brick piers were built this time; the caisson was quite strong enough on its own. (With 53,000 tons on its back, it showed not the slightest sign of deflection in the roof.) But about a third of the space was filled with stones, earth, and sand left inside during the sinking. With the concrete going in at the rate of one hundred cubic yards a day, Roebling figured to have the entire job done by early July. The saying was that the concrete would keep pouring into the caisson until there was room enough left for one last Irishman, who would make his final exit by one of the water shafts.
But some time before that happened, Roebling suffered another attack of the bends. There is nothing in the official record to indicate just when it happened, only that it was late spring, while the concrete work was going on. Apparently he collapsed again, as he had the night of the Brooklyn caisson fire, and he was immediately taken back to Brooklyn on the ferry.
Who was on hand to help him is not known. There would be nothing said of the incident in the papers, suggesting that perhaps he and the others wanted no more adverse publicity than they already had or that they thought the seizure would soon pass. He himself made only the briefest mention of what happened in a report published later that fall. The attack, he said, resulted from a stay of several hours in the caisson, suggesting that he still believed the time spent below was the determining factor and had never accepted Smith’s theory on speed of decompression. “Relief from the excruciating pain,” Roebling wrote, “was afforded in his [the writer’s] case by a hypodermic injection of morphine in the arm, where the pain was most intense, and a further stupefaction by morphine, taken for twenty-four hours internally until the pains abated.” According to Emily Roebling, however, in an account written a few years later, his condition was so serious the night of the attack that he was expected to die before morning.
There is no telling whether Smith was called back, whether the idea of returning to pressure (“the heroic mode”) was even considered, or if so, why it was rejected in favor of drugging the patient into a stupor.
For several days more Roebling lay near death in the same Hicks Street house where his father had died. His assistants came and went. Somebody was with him at all times. Little hope was held out for him. In some of the things written about him a generation later, it would be said that Roebling remained painfully paralyzed, a total invalid from this point on. But the record shows this was not the case. In another few days, much to everyone’s amazement, he went back to work.
Once when he was seventeen, his father had been faced with a cholera epidemic at Niagara Falls. More than sixty people had died in the first week and the doctors seemed incapable of doing anything to help. “The great secret,” his father had written to Charles Swan, was to “keep off fear.” His father, too, would have succumbed with the rest, according to one man who was there, had it not been for his uncommon powers of concentration. “He determined not to have it,” the man wrote. John Roebling had spent one whole night walking up and down his room, fighting to rid his mind of the very thought of cholera. The incident made an enormous impression on the gentleman who witnessed it and on everyone back in Trenton when the story was told there. Now it seems Washington Roebling too had “determined not to have it.” Other men might resign themselves to their fate, he could not.
Through the first weeks of summer the attacks kept recurring, however, and he suffered intensely. He made no public mention of this, nor did anybody else. It is only from comments made in private correspondence years afterward that anything is known of his extreme physical suffering. To judge by the Bridge Company’s record books and occasional items in the papers, he was carrying on as though nothing were the matter. It was during this time, for instance, that his report exonerating the management of Bridge Company purchases was read before the board, and knowing this, one cannot but wonder if his physical and emotional torment, the anxiety Emily described, did not have something to do with the discrepancies between that report and some of the things he would say privately much later on.
On July 12 the filling in of the New York caisson was completed and apparently under the personal supervision of the Chief Engineer. The whole task of sinking the caisson had taken 221 days.
He took two weeks off and went with Emily to Saratoga. He was somewhat improved when they returned but that lasted only briefly. By September he was staying home two and three days a week. Still his condition remained a private matter. To judge by the official records and items in the papers the Chief Engineer was very much on the job.
On September 3 bills amounting to $50,000 were ordered paid, on being certified by the Chief Engineer. On September 17 the Chief Engineer was directed to solicit bids for the anchor bars for the New York anchorage and the Chief Engineer and the General Superintendent were authorized to award the contract to the lowest bidder. On October 8 the Executive Committee authorized the president of the Bridge Company to execute a contract with the Bodwell Granite Company of Maine, according to specifications prepared by the Chief Engineer. An agreement made by the Chief Engineer with Louis Osborne of East Boston, for building an expensive double hoisting engine, was also approved, and a number of substantial bills were ordered paid, after being certified by the Chief Engineer.
In late November it was Roebling who ordered that work on the Brooklyn tower be suspended for the winter. The tower by then had reached a height of about 145 feet, or well beyond the level where the bridge deck would be. It was no longer a solid flat-topped shaft. Now the beginning of the great archways could be seen thrusting upward like three immense teeth separated by the two gaping spaces left for the roadways.
It was in December, the same month the Committee of Investigation presented its findings, that work on the New York tower was halted, on account of the weather, at a height of nearly sixty feet. And it was in December that Washington Roebling found he was unable to go down to the bridge anymore. His condition was very serious now, extremely puzzling, and a closely guarded secret among the relative handful of men who were running things inside the bridge offices.
The sudden, violent cramps, the awful dizziness and vomiting had ended after the first horrible days in early summer, just as had been the experience of every other victim from the caisson, indeed as had been his own experience the time before. But the pains and the numbness had continued, coming and going, in his arms and legs primarily. He tired rapidly. He was sick at his stomach much of the time. He became extremely irritable and distraught over the slightest problems or inconveniences and slipped into moods of profound gloom that lasted for days. By December he was a very sick man. Still, he refused to give up. “He was never known to give in or own himself beaten,” the men at the mill had said of his father.
Emily Roebling went to see Henry Murphy, to talk privately about the situation. Her husband was determined to continue as Chief Engineer, she said. Murphy told her that that would be agreeable with him, just so long as nothing went wrong at the bridge. She expected his troubles would last but a short time.
Total rest was the only cure prescribed for him through that winter, and Emily was apparently about the only person he wanted anywhere near him for any length of time. The doctors kept telling her that he had little chance of recovery, that she should be prepared for the worst, while he himself had become obsessed with the idea that he would not live to see the bridge finished. And knowing better than anyone how incomplete the plans and instructions for the remaining work still were, he spent that entire winter writing down, in his minute, meticulous hand, all that had to be done, filling page after page with the most exacting, painstaking directions for making the cables, for assembling the complicated components of the superstructure, and illustrating these with detailed freehand drawings and diagrams.