The Canadian Journal of Medicine and Surgery A JOURNAL PUBLISHED MONTHLY IN THE INTERESTS OF VOL. XVII. TORONTO, APRIL, 1905. NO 4. Original Contributions. NIELS RYBERG FINSEN-HIS LIFE and WORK.* BY CHARLES R. DICKSON, M.D., TORONTO, Electrologist to Toronto General Hospital, Hospital for Sick Children, St. Michael's Hospital; Fellow and ex-President of American Electro-Therapeutic Association, Member of Canadian Institute, etc. THE beneficial action of sunlight, both in maintaining health and in combating various diseases, has been recognized from time immemorial. The ancient Greeks anointed their bodies and exposed themselves to sunshine on the flat roofs of their houses, both for pleasure and health. The Romans also indulged in the sunbath, frequently following it with cold sponging, according to Vestricius and Cicero. Later, they had special buildings, called solaria, in which they took the Heliosis or sun-bath. Herodotus, C. Aurelian, and Antyllus recommend sun-baths in diseases of the skin and other affections, and many of the writers of antiquity advise the use of the sun-bath as a curative agent.† This early belief in the therapeutic value of the rays of the sun is well nigh universal. Natives of South and Central America and Mexico lie full length on their backs for hours in the blazing tropical sun, as a remedy for consumption, a method said to antedate the advent of the Spaniard. And in China, Japan, Hayti, and Mexico, the injurious effects of sun * Revised Abstract of a paper read at meeting of Canadian Institute, Toronto, Jan. 28, 1905. ↑ Freund, "Radio-Therapy." Rogers, "Luco-Therapy." light in certain conditions are also known, so that while some patients are given sun-baths, others are kept from the light. Systematic phototherapy dates from the beginning of the nineteenth century, when Professor Lobel, of Jena, set forth definitely the indications and contraindications for light treatment, and described a special apparatus for the purpose, since which time much has been accomplished in placing phototherapy upon a scientific basis. But it remained for the immortal Finsen to gather the threads of evidence of the powerful influence of light upon health, to crystalize the discoveries of others, and to carry on his own ingenious, extended, and most strangely simple series of observations. Born on the Faroe Islands, and living until his twenty-first year in Iceland, sunlight always had a great charm for him, and the sunless days depressed him greatly. Even as a boy he noted the action of the sun's rays upon certain animals. He spent eight years at the University of Copenhagen, in Denmark, graduating in 1890 as Doctor of Medicine, thirty years of age, but already a confirmed invalid since the age of twenty-three, with heart, liver and organs of digestion hopelessly affected, and active practice of his profession absolutely impossible. For three years after graduation he acted as Prosector of Anatomy under Professor Chiewitz at the university, and they still use there a dissecting knife invented by him. But, though handicapped so greatly bodily, he possessed keen powers of observation, the faculty of investigation highly developed, a rare intelligence, and an indomitable will, in spite of almost constant physical suffering. Finsen was always keenly anxious to probe the mysteries of light, and from before the close of his student days had been experimenting with it. His first investigations dealt with the injurious action of the so-called chemical rays of light, of the blue, violet, and especially the ultra-violet parts of the spectrum, the most refrangible; where the chemical effect is at the maximum, the heating effect at the minimum; while at the other extremity of the spectrum the opposite phenomena obtain, the red and ultra-red rays being least refrangible, and the chemical effect at the minimum. In July, 1893, he had set forth some striking theories as to the action of light, and later, in 1894, he expounds and elaborates them, first drawing attention to the fact that "with the exception of the influence of light upon plants and upon the organ of vision, our knowledge of the physiological action of light and its effects, whether good or bad, is very limited." He considers the injurious influence of the chemical rays upon the animal organism, first, not because he regards this 1. Thorshavn, Stromö, Capital of the Faröes, from the Harbor, Government House. 2. South Harbor, Fish Stores, etc. 3. The Stream through Thorshavn. 4. Reykjavik, Capital of Iceland. 6. Copenhagen, Capital of Denmark. 5. Business Quarter of Reykjavik. 7. Finsen's Home, Copenhagen. 8. Niels Ryberg Finsen, "The Wolf-Slayer." Born Dec. 15th, 1860, at Thorshavn, Stromö, Faroe Islands. Died Sept. 24th, 1904, at Copenhagen, Denmark. property as their only influence, but because it constitutes the very foundation of the subject.* He notes that the deleterious or fatal influence of light upon the majority of bacteria is already known: that Duclaux, in 1885, had said that "sunlight is the best, cheapest, and most universally applicable bactericidal agent that we have;" that Downes and Blunt, in 1878, had shown that this effect was almost exclusively due to the chemical rays; that Graber, in 1883, found that earthworms in a box covered with strips of colored glass representing the colors of the spectrum, always crawled to the darkest places, viz., under the red glass, and Dubois, in 1890, had shown that the proteus was least comfortable in white light. Brucke, in 1851, had explained that the chameleon changed its color by moving the pigment cells in its skin nearer to the surface, thus protecting itself against a disagreeable light impression; Paul Bert, in 1878, noted that while red and yellow light did not influence the pigment cells, blue and violet rays caused strong reaction, and in 1887 observed that if half of its body were illuminated through red glass and half through blue, that under the red remains a long time whitish, while that under the blue becomes blackish almost instantly. Finsen had noticed that horses and horned cattle suffered from solar erythema, limited almost exclusively to non-pigmented parts of the skin. Wedding, in 1883, and Virchow later, observed that cattle and sheep fed on buckwheat are subject to vesicular cutaneous eruptions, more marked in the whiter animals and those exposed to light. Those kept in the dark were not affected, and a white cow coated on one side with tar, had the exanthem only on the opposite side. Livius Furst noted that in preparing animal vaccine, calves with a light skin were preferred, because pustules did not develop well upon those with a dark hide. Volkmann learned this practically in 1891, but did not explain it. Unna, of Hamburg (1885); Widmark, of Stockholm (1889), and Hammer, of Stuttgart (1891) definitely demonstrated that the chemical rays, particularly the ultra-violet, are exclusively the cause of erythema solare, or eczema solare, and physiological pigmentation of parts of the skin exposed to light, explorers in polar regions and tourists on glaciers suffering severely from erythema caused by the reflection of sunlight by the ice, even with a temperature below zero. Finsen regarded pigmentation as a protection from injurious action of the chemical rays, the coloring matter preventing them from penetrating too deeply, and proved this to his satisfaction. Painting a band of Indian ink around a part of his arm unac *Finsen, "Photo-Therapy." customed to direct sunlight, he exposed it to a hot sun for about three hours. Removing the Indian ink disclosed a white band of normal skin, while that on either side was red, and later became inflamed, painful and swollen, remaining so several days, and finally becoming much pigmented, the white band remaining quite normal. On again exposing the arm without blackening it, the white zone became the seat of inflammation, while the pigmented parts were not affected except to become more pigmented. Oarsmen experience the protection of pigmentation. Furred animals, whales, reptiles, birds and fish are colored most on the side most exposed to the sun; fish require this protection because water, while it absorbs the red and ultra-red rays largely, allows the ultra-violet to pass freely. In plant life, pigmentation is also provided for protection against too much light. The acute effects of chemical rays upon human skin vary from a feeble irritation to inflammation with epidermal desquamation, depending upon the intensity of the light, the proportion of chemical rays it contains, the duration of exposure, amount of pigmentation and thickness of epidermis. Ordinary lamps give proportionately less, and electric are light more chemical rays than the sun. The inflammation, unlike all other of similar duration, does not develop immediately, only attains its greatest intensity from twelve to twenty-four hours after exposure, develops only upon parts directly exposed to luminous rays, and leaves a pigmentation of the skin. It is thus unlike that caused by heat rays. In smelting metals in an electrical furnace, men suffer severely from the effects of the light upon their skin and eyes. Widmark proved that this was due to the action of ultra-violet rays alone, and not to heat rays. As long ago as 1859, Charcot expressed the opinion that it was the chemical and not the heat rays that occasioned erythema solare, and that the dermatitis. caused by a very strong electric light is identical with erythema solare, but it was not till 1889 that Widmark gave the scientific proof thereof. An electric arc of twelve thousand candle power was used; by passing its light through a thick enough layer of water, the heat rays were absorbed, and by passing the light through a plate of common glass, the ultra-violet rays were absorbed and thus excluded. When the heat rays alone were excluded, skin subjected to the influence of the light developed the characteristic inflammation, but when only ultra-violet rays were excluded, the skin exposed to the light was unaffected. Having considered the microscopic phenomena of light and the form of inflammation caused by a special irritant, Finsen turned to histological changes, to determine whether the inflam |