That this power, like any other, had its perils, and that nature, if not man, was awake to them, he proved by some simple experiments with sunburn. He showed that the tan which boys so covet was the defence the skin puts forth against the blue ray. The inflammation of sunburn is succeeded by the brown pigmentation that henceforth stands guard like the photographer"s ruby window, protecting the deeper layers of the skin. The black skin of the negro was no longer a mystery. It is his protection against the fierce sunlight of the tropics and the injurious effect of its chemical ray.
Searching the libraries in Copenhagen for the records of earlier explorers in his field, and finding little enough there, Finsen came across the report of an American army surgeon on a smallpox epidemic in the South in the thirties of the last century. There were so many sick in the fort that, every available room being filled, they had to put some of the patients into the bomb-proof, to great inconvenience all round, as it was entirely dark there. The doctor noted incidentally that, as if to make up for it, the underground patients got well sooner and escaped pitting. To him it was a curious incident, nothing more. Upon Dr. Finsen, sitting there with the seventy-five-year-old report from over the sea in his hand, it burst with a flood of light: the patients got well without scarring _because_ they were in the dark. Red light or darkness, it was all the same. The point was that the chemical rays that could cause sunburn on men climbing glaciers, and had power to irritate the sick skin, were barred out. Within a month he jolted the medical world by announcing that smallpox patients treated under red light would recover readily and without disfigurement.
The learned scoffed. There were some of them who had read of the practice in the Middle Ages of smothering smallpox patients in red blankets, giving them red wine to drink and hanging the room with scarlet. Finsen had not heard of it, and was much interested.
Evidently they had been groping toward the truth. How they came upon the idea is not the only mystery of that strange day, for they knew nothing of actinic rays or sunlight a.n.a.lyzed. But Finsen calmly invited the test, which was speedy in coming.
They had smallpox in Bergen, Norway, and there the matter was put to the proof with entire success; later in Sweden and in Copenhagen.
The patients who were kept under the red light recovered rapidly, though some of them were unvaccinated children, and bad cases. In no instance was the most dangerous stage of the disease, the festering stage, reached; the temperature did not rise again, and they all came out unscarred.
Finsen pointed out that where other methods of treatment such as painting the face with iodine or lunar caustic, or covering it with a mask or with fat, had met with any success in the past, the same principle was involved of protecting the skin from the light, though the pract.i.tioner did not know it. He was doing the thing they did in the middle ages, and calling them quacks.
It is strange but true that Dr. Finsen had never seen a smallpox patient at that time, but he knew the nature of the disease, and that the sufferer was affected by its eruption first and worst on the face and hands--that is to say, on the parts of the body exposed to the light--and he was as sure of his ground as was Leverrier when, fifty years before, he bade his fellow astronomers look in a particular spot of the heavens for an unknown planet that disturbed the movements of Ura.n.u.s. And they found the one we call Neptune there.
Presently all the world knew that the first definite step had been taken toward harnessing in the service of man the strange force in the sunlight that had been the object of so much speculation and conjecture. The next step followed naturally. In the published account of his early experiments Finsen foreshadows it in the words, "That the beginning has been made with the hurtful effects of this force is odd enough, since without doubt its beneficial effect is far greater." His clear head had already asked the question: if the blue rays of the sun can penetrate deep enough into the skin to cause injury, why should they not be made to do police duty there, and catch and kill offending germs--in short, to heal?
Finsen had demonstrated the correctness of the theory that the chemical rays have power to kill germs. But it happens that these are the rays that possess the least penetration. How to make them go deeper was the problem. By an experiment that is, in its simplicity, wholly characteristic of the man, he demonstrated that the red blood in the deeper layers of the skin was the obstacle. He placed a piece of photographic paper behind the lobe of his wife"s ears and concentrated powerful blue rays on the other side. Five minutes of exposure made no impression on the paper; it remained white. But when he squeezed all the blood out of the lobe, by pressing it between two pieces of gla.s.s, the paper was blackened in twenty seconds.
That night Finsen knew that he had within his grasp that which would make him a rich man if he so chose. He had only to construct apparatus to condense the chemical rays and double their power many times, and to apply his discovery in medical practice. Wealth and fame would come quickly. He told the writer in his own simple way how he talked it over with his wife. They were poor. Finsen"s salary as a teacher at the university was something like $1200 a year. He was a sick man, and wealth would buy leisure and luxury. Children were growing up about them who needed care. They talked it out together, and resolutely turned their backs upon it all. Hand in hand they faced the world with their sacrifice. What remained of life to him was to be devoted to suffering mankind. That duty done, what came they would meet together. Wealth never came, but fame in full measure, and the love and grat.i.tude of their fellow-men.
There is a loathsome disease called lupus, of which, happily, in America with our bright skies we know little. Lupus is the Latin word for wolf, and the ravenous ailment is fitly named, for it attacks by preference the face, and gnaws at the features, at nose, chin, or eye, with horrible, torturing persistence, killing slowly, while the patient shuts himself out from the world praying daily for death to end his misery.
In the north of Europe it is sadly common, and there had never been any cure for it. Ointments, burning, surgery--they were all equally useless. Once the wolf had buried its fangs in its victim, he was doomed to inevitable death. The disease is, in fact, tuberculosis of the skin, and is the most dreadful of all the forms in which the white plague scourges mankind--was, until one day Finsen announced to the world his second discovery, that lupus was cured by the simple application of light.
It was not a conjecture, a theory, like the red-light treatment for smallpox; it was a fact. For two years he had been sending people away whole and happy who came to him in despair. The wolf was slain, and by this silent sufferer whose modest establishment was all contained within a couple of small shanties in a corner of the city hospital grounds, at Copenhagen.
There was a pause of amazed incredulity. The scientific men did not believe it. Three years later, when the physician in charge of Finsen"s clinic told at the medical congress in Paris of the results obtained at the Light Inst.i.tute, his story was still received with a polite smile. The smile became astonishment when, at a sign from him, the door opened and twelve healed lupus patients came in, each carrying a photograph of himself as he was before he underwent the treatment. Still the doctors could not grasp it. The thing was too simple as matched against all their futile skill.
But the people did not doubt. There was a rush from all over Europe to Copenhagen. Its streets became filled with men and women whose faces were shrouded in heavy bandages, and it was easy to tell the new-comers from those who had seen "the professor." They came in gloom and misery; they went away carrying in their faces the sunshine that gave them back their life. Finsen never tired, when showing friends over his Inst.i.tute, of pointing out the joyous happiness of his patients. It was his reward. For not "science for science"s sake," or pride in his achievement, was his aim and thought, but just the wish to do good where he could. Then, in three more years, they awarded him the great n.o.bel prize for signal service to humanity, and criticism was silenced. All the world applauded.
"They gave it to me this year," said Finsen, with his sad little smile, "because they knew that next year it would have been too late." And he prophesied truly. He died nine months later.
All that is here set down seems simple enough. But it was achieved with infinite toil and patience, by the most painstaking experiments, many times repeated to make sure. In his method of working Finsen was eminently conservative and thorough. Nothing "happened" with him. There was ever behind his doings a definite purpose for which he sought a way, and the higher the obstacles piled up the more resolutely he set his teeth and kept right on.
"The thing is not in itself so difficult," he said, when making ready for his war upon the wolf, "but the road is long and the experiments many before we find the right way."
He took no new step before he had planted his foot firmly in the one that went before; but once he knew where he stood, he did not hesitate to question any scientific dogma that opposed him, always in his own quiet way, backed by irrefutable facts. In a remarkable degree he had the faculty of getting down through the husk to the core of things, but he rejected nothing untried. The little thing in hand, he ever insisted, if faithfully done might hold the key to the whole problem; only let it be done _now_ to get the matter settled.
Whatever his mind touched it made perfectly clear, if it was not so already. As a teacher of anatomy he invented a dissecting knife that was an improvement on those in use, and clamps for securing the edges of a wound in an operation. As a rifle shot he made an improved breech; as a physician, observing the progress of his own disease, an effective blood powder for anaemia. At the Light Inst.i.tute, which friends built for him, and the government endowed, he devised the powerful electric lamps to which he turned in the treatment of lupus, for the sun does not shine every day in Copenhagen; and when it did not, the lenses that gathered the blue rays and concentrated them upon the swollen faces were idle. And gradually he increased their power, checking the heat rays that would slip through and threatened to scorch the patient"s skin, by cunning devices of cooling streams trickling through the tubes and the hollow lenses.
Nothing was patented; it was all given freely to the world. The decision which he and his wife made together was made once for all.
When the great n.o.bel prize was given to him he turned it over to the Light Inst.i.tute, and was with difficulty persuaded to keep half of it for himself only when friends raised an equal amount and presented it to the Inst.i.tute.
Finsen knew that his discoveries were but the first groping steps upon a new road that stretched farther ahead than any man now living can see. He was content to have broken the way. His faith was unshaken in the ultimate treatment of the whole organism under electric light that, by concentrating the chemical rays, would impart to the body their life-giving power. He himself was beyond their help. Daily he felt life slipping from him, but no word of complaint pa.s.sed his lips. He prescribed for himself a treatment that, if anything, was worse than the disease. Only a man of iron will could have carried it through.
A set of scales stood on the table before him, and for years he weighed every mouthful of food he ate. He suffered tortures from thirst because he would allow no fluid to pa.s.s his lips, on account of his tendency to dropsy. Through it all he cheerfully kept up his labors, rejoicing that he was allowed to do so much. His courage was indomitable; his optimism under it all unwavering. His favorite contention was that there is nothing in the world that is not good for something, except war. That he hated, and his satire on the militarism of Europe as its supreme folly was sharp and biting.
Of such quality was this extraordinary man of whom half the world was talking while the fewest, even in his own home city, ever saw him. Fewer still knew him well. It suited his temper and native modesty, as it did the state of his bodily health, to keep himself secluded. His motto was: "_bene vixit qui bene latuit_--he has lived well who has kept himself well hidden"--and his contention was always that in proportion as one could keep himself in the background his cause prospered, if it was a good cause. When kings and queens came visiting, he could not always keep in hiding, though he often tried. On one of his days of extreme prostration the dowager empress of Russia knocked vainly at his door. She pleaded so hard to be allowed to see Dr. Finsen that they relented at last, and she sat by his bed and wept in sympathy with his sufferings, while he with his brave smile on lips that would twitch with pain did his best to comfort her. She and Queen Alexandra, both daughters of King Christian, carried the gospel of hope and healing from his study to their own lands, and Light Inst.i.tutes sprang up all over Europe.
In his own life he treated nearly nineteen hundred sufferers, two-thirds of them lupus patients, and scarce a handful went from his door unhelped. When his work was done he fell asleep with a smile upon his lips, and the "universal judgment was one of universal thanksgiving that he had lived." He was forty-three years old.
When the news of his death reached the Rigsdag, the Danish parliament, it voted his widow a pension such as had been given to few Danes in any day. The king, his sons and daughters, and, as it seemed, the whole people followed his body to the grave. The rock from his native island marks the place where he lies. His work is his imperishable monument. His epitaph he wrote himself in the speech another read when the n.o.bel prize was awarded him, for he was then too ill to speak.
"May the Light Inst.i.tute grasp the obligation that comes with its success, the obligation to maintain what I account the highest aim in science--truth, faithful work, and sound criticism."