The law now on our statute books seems to contemplate a lock canal. In my judgment a lock canal as herein recommended is advisable. If the Congress directs that a sea-level canal be constructed, its direction will, of course, be carried out. Otherwise, the canal will be built on substantially the plan for a lock canal outlined in the accompanying papers, such changes being made, of course, as may be found actually necessary.
In June 1906 Congress finally decided for a high-level canal, and the controversy was officially closed. But the friends of the sea-level scheme were by no means silenced. Whenever any serious difficulty occurred in the construction of the canal on the lock principle their voices were heard again. In fact, the conflict cannot be said to have ended until 1909, and even then it is not certain that the sea-levellers modified their convictions.
CHAPTER IX.
MAN AND THE GNAT.
Almost at the beginning of their great task the Americans were faced with a problem which involved the success or failure of the whole enterprise. I have said something about the climate and health conditions at the isthmus. It is fairly certain that yellow fever and malaria would have wrecked the French undertaking even if there had been no other obstacles to its success. It is not less probable that if the Americans had been in no better a position to wage war with these plagues, their work at the isthmus would also have been in vain. The French had built excellent hospitals and provided efficiently for the comfort and recovery of those who were stricken with these diseases. But being totally ignorant of the sources and method of transmission of malaria and yellow fever, they could do nothing effectual in the way of prevention and eradication. They could only take the individual victim when they found him and do their best to cure him. They still believed that malaria was produced by climatic conditions, by marshy emanations, mists, and so forth. The fleecy clouds which gather round the isthmian hills in the rainy season were given the very undeserved title of "the white death" by the French workers at the isthmus. Yellow fever, again, was just as mistakenly attributed to the climate, and especially to filthy ways of living. It is not surprising that, with these misconceptions, medical skill should have been almost useless during the French occupation, and that the employees at the isthmus should have died in their thousands.
But since the days of the Lesseps company, science had thrown a flood of light on the nature of these tropical scourges and the secret of their transmission. As these medical and scientific pioneers made a Panama Canal possible, though their names are not directly linked with its construction, we may look back for a few moments at their triumphs of discovery. The credit for first discovering that malaria is not due to poisonous emanations or contagion but is carried from people infected with the disease by the anopheles mosquito belongs to Major (now Sir) Ronald Ross, formerly of the Indian Medical Service, who devoted himself to this subject during the last years of the 19th century. By a series of experiments he proved that malaria is due to the presence in the human blood of an organism which is conveyed from person to person by this mosquito, and that the mosquito is harmless unless it has become infected with the germ by biting a person who has caught malaria. The value of this discovery was soon shown by practical applications. Major Ross was engaged by the Suez Canal Company to deal with the malaria which had become firmly established at Ismailia, a little town of 10,000 inhabitants on that canal. No fewer than 2,500 cases had been supplied in one year by this small population. The new methods founded on the new discovery proved so effectual that in three years the disease was stamped out, and there has been no relapse ever since. The same results were achieved at Port Said.
Now, if malaria is thus caused by mosquito bite, there was some à priori reason for thinking that yellow fever might be transmitted in the same way. At any rate the insect was again laid under a very grave suspicion. The opportunity for studying this further question was afforded during the Spanish-American war, when a serious outbreak occurred among the troops occupying Havana, in Cuba. The doctors were quite unable to deal with this most terrible of all diseases. Knowing nothing whatever of its cause, their treatment of it could be only experimental and casual. So a board of inquiry was formed consisting of four army surgeons serving in Cuba—Walter Reed, James Carroll, Jesse W. Lazear, and Aristides Agramonte. The experiments were begun in June 1900, and continued into the next year. Of these four, Dr. Agramonte was not liable to the disease, and Dr. Reed was called away on duty to Washington. The other two determined to experiment on their own persons rather than risk the lives of other people.
Dr. Carroll first allowed himself to be bitten by the mosquitoes, not the anopheles but another variety known as the stegomyia. He fell ill with a bad attack of yellow fever, which very nearly cost him his life. Later, in the yellow fever hospital, Dr. Lazear deliberately allowed a mosquito to feed on his hand. In four days he was down with the disease in so acute a form that he died of it—a true martyr, if ever there was, to the cause of science and the welfare of mankind. These and other experiments proved conclusively that yellow fever, like malaria, is transmitted by mosquito bites, but it was still uncertain how soon after biting an infected person the mosquito becomes itself harmful and how soon a person stricken with malaria is able to infect a healthy mosquito. So further experiments were necessary, and volunteers were invited to offer themselves for this service. Everybody in the army knew what had happened to Doctors Carroll and Lazear, but in spite of this plenty of willing martyrs appeared. The first to present themselves were two young soldiers from Ohio, John R. Kissinger and John J. Moran. Dr. Reed talked the matter over with them, explaining fully the danger and suffering involved, and stating the money consideration offered by General Wood. Both young men declared that they were prepared to undergo the experiment, but only on condition that they should receive no pecuniary reward. When he heard this declaration, Dr. Reed touched his hat with profound respect, saying, "Gentlemen, I salute you!"[8] Kissinger took the disease from the mosquito bites, and recovered. A room was prepared for Moran, a sort of mosquito den into which fifteen gnats, all suffering from yellow fever, had been admitted. Major Reed describes what happened:—