taking as they were brilliant. Ross first of all found that the mosquito in imbibing human blood ingested the parasite, and he observed the formation of the flagellated body in the stomach of the mosquito. Thus he confirmed Manson's notion of the flagellum being connected with the extra-corporeal life of the parasite. It had been known for some time that birds suffered from plasmodial disease and Ross determined to work out the problem on birds. The evolution of one of these avian parasites, the halteredium, had been worked out by McCallum, of Johns Hopkins, and another, Proteosoma labbe, had been studied by the Italian observers. Ross chose to make his experiments with proteosoma.

Ross allowed birds afflicted with proteosoma to be attacked by mosquitoes, and again found the malarial organism to enter the mosquito's stomach. An hour later, examining this mosquito, he found certain oval pigmented bodies in the muscular lining of the stomach, which he inferred were a developed stage of the proteosoma, for in hundreds of test experiments these pigmented bodies only occurred in mosquitoes fed on proteosomatous birds. That these bodies were evolutionary forms of proteosoma was almost confirmed by what was known of the evolution of halteridium, the other malarial parasite of birds. In this organism, after the flagellum had broken away, it entered the pigmented halteridiæ, and these being transformed into traveling vermicules possessed the power of entering the corpuscles. In other words a sexual process resembling the embedding of the spermatozoon in the ovum took place. Ross inferred the same thing to occur in proteosoma and that the traveling vermicules entered the mosquito's stomach and there became the pigmented bodies. The further course of the evolution of the proteosoma in the stomach is highly interesting. It grows in size and projects rounded bodies beyond the stomach walls. These Ross termed proteosoma coccidia. These coccidia undergo changes of appearance. Pigment comes and then disappears, but the coccidia finally burst and from them emerge the germinal vermicules. These vermicules Ross found practically infested all the tissue of the mosquito and what was of highest importance these forms were discovered in the venenosalivary glands of the mosquito. The climax of these brilliant investigations was now within easy reach. Ross allowed mosquitoes to feed on birds afflicted with proteosoma, and after a few days he fed them on birds whose blood was void of parasitic infection. The blood of the latter in a ew days was filled with proteosoma, thus establishing the fact that the mosquito acted as an extra-corporeal and intermediate host of the malarial parasite of birds.

Two or three months later the scene in this scientific drama changes from India where Ross had made his mosquito dissections, to Italy once more. In a gauze caged room in the Ospitale di San Spirit, under the direction of Dr. Bignami, an attempt is being made to transmit by mosquito innoculation the parasite to man. The patient is confined in the cage and mosquitoes are brought to feed on him. Nothing results. A week or two later another experiment is made and nothing occurs. A third experiment is made on a man named Sola, he is thoroughly bitten

by mosquitoes, he developes a little malaise and headache but that is all. These failures led to the next important step in this investigation, a more complete study of the mosquito of which there are many varieties. Ross. in India, had come to the conclusion that the common mosquito was a harmless insect, for his experiments were only successful with the large grey mosquito. Grassi, an associate of Bignami, captured at Maccarese, a place about twenty miles from Rome, on the Civita Vecchia road, where a severe form of estivo-autumnal fever prevails, three species of mosquitoes. With these the fourth experiment was made. On the first of November, 1898, a patient bitten by these mosquitoes had a severe rigor, and on November 3rd his temperature reached 105 degrees. On the evening of this day the estivo-autumnal parasite was found in his blood. Thus did Ross's discovery receive complete and final corroboration.

67 Cass St.

NEILS R. FINSEN.

By H. ROCKWELL VARNEY, M. D.

Detroit.

To Professor Neils R. Finsen, the world at large is indebted for the scientific research and therapeutic application of the Light treatment which bears his name; and instead of applying his wonderful results toward financial gain, he gave to the medical profession the benefit of his discoveries.

He was born on the Island of Faroe, near Iceland, where his early life was spent. At the age of twenty, he went to Copenhagen and entered the university, taking a course in medicine, but as his health was undermined after he graduated, instead of engaging in active practice, he was obliged to accept a position as instructor in anatomy in the university.

The little leisure he had, was spent in scientific research. The effect of light had always a great fascination for him. This was probably due to the fact that he had lived in a country of wind and storm, which the sun favored at short and infrequent intervals. His interest in its effect is made manifest by these words. "On a cloudy day let the sun suddenly break through, and see the change. Insects that were drowsy, wake up and take wings; the snakes come out to sun themselves, the birds burst into song; we ourselves, feel as if a burden had been lifted." Being of an enquiring turn of mind, he asked nature why, and decided to study the ants, lizards, and earth-worms. Nor did his interest in the subject ever fail, and it was during his career as instructor at the university, that he found in the medical library, a pamphlet containing the report of Dr. Pictou, of New Orleans, of some soldiers who, while confined in dungeons, broke out with small-pox, and after recovery, it was discovered that they were free from scars. This was in accordance with some of Finsen's theories regarding the effect of light, and was a basis for further investigation. He decided that the soldiers were not pitted because of the exclusion of all light, and especially the blue or actinic rays, for he had already proven that it was these rays that disturbed earth-worms,

while they remained undisturbed in the red rays. His query was, "If the blue rays disturb the worm, why would they not irritate an inflamed skin?" He at once began the study of the effect of these chemical rays upon eruptive diseases of the skin, especially small-pox. In the latter part of the year 1893, he gave out his first reports of these investigations. which, though based purely upon theoretical grounds, as he had never seen a case of small-pox up to this time, were that patients suffering with this disease will be free from scars, if all rays except the red rays are excluded from them.

During an epidemic of small-pox among the soldiers, his theories were tested by Dr. Stevendsen, assistant surgeon in the army, who, by means of red shades, excluded all other rays of light from his patients. and the results of his experiment proved a triumph for Finsen who was then given a pension of $1,200 a year from the Danish government.

Dr. Stevendsen's report of the red light treatment was that "The period of suppuration, the most dangerous and painful stage of the smallpox, did not appear; there was no elevation of temperature and no edema. The patients entered the stage of convalescence immediately after the stage of vaccination, which seemed a little prolonged. The hideous scars were avoided." Later, control tests were made, and it was proven that patients exposed to very little daylight, suffered suppuration and scarring.

After the reports of these experiments had brought Finsen into such. prominence, it was no longer necessary for him to continue teaching, and he was able to devote all of his time, though handicapped seriously by ill-health, to realizing his hopes of discovering the virtues of the chemical rays of light, and their application to disease.

That sunlight would kill bacteria was long before an established fact, and Finsen's efforts were concentrated upon proving that this action was due entirely to the blue, violet, and ultra-violet rays. Plate culture of bacillus prodigiosus were killed by the July sun in one hour and a half, whereas, by concentrating this same light through lenses, after excluding all useless rays, the same baccilli and others were killed in from two to three seconds.

His next step was to estimate the penetrating power of the rays. To test this, he experimented, not only upon himself, but upon his wife, until he was satisfied that there were decided limitations to this power of penetration. He next proved that concentrated electric light is a more powerful agent than sunlight, and that tissues are penetrated much more quickly and deeper if the blood is first pressed from them.

Owing to the limitations of this power of penetration, he directed his attention chiefly to diseases of the skin that were of germ origin, selecting first, that heretofore unresponsive, dread disease, Lupus. His first patient was a man who had been suffering for eight years, and who had been subjected to every known treatment. His apparatus was a very crude affair, the red rays being filtered out through blue water, but the results met his fullest expectations, and another decided triumph was scored, and recognized by the people, for in a month's time the Finsen

Light Institution was established in Copenhagen, and the Danish government has continued to support, enlarge and beautify this institution until at the present time, it is heard of throughout all lands.

So carefully and scientifically did Finsen conduct his experiments that no one thus far, has been able to improve upon his apparatus, yet it has been attempted by thousands.

Finsen cultivated a field already ploughed by General Pleasanton, in the medical profession which has been productive of results, which have benefitted the whole of the civilized world. The number of actual cures to date, exceeds those accomplished by any other form of treatment, and these will ever establish him among the highest ranks of the world's benefactors. When we consider that he was ever struggling against disease that had attacked all of his vital organs, that for years, every particle of food he ate was weighed, we should place him among the martyrs. That he expected and hoped to accomplish more, had not death cut short his brilliant career, is evident when we consider his theories regarding the penetrating power of light. His aim was to discover a means of penetrating the body through and through, so as to reach internal affections; and this he has bequeathed to other investigators as food for thought and experiment.

Finsen's is a case of history repeating itself in that any great good is accomplished only by struggles and conflicts of the individual or the masses. Poor he was, broken in health, yet ever striving to make discoveries, not for individual gain, but to benefit mankind. It was not until 1893 that he was free to devote his entire time to his investigations, and not until 1903, a year previous to his death, that he was made financially independent by being rewarded the Nobel prize in medicine.

420 Woodward Ave.

IVAN PETROVITCH PAWLOW. (PAVLOFF).

By HOMER E. SAFFORD, M. D.
Detroit.

The fourth award of the Nobel prize for the advancement of physiology and medical science fell to a man whose name, because of the barriers set up by a strange language, is little known to English-speaking peoples aside from the few who follow closely the progress of physiology. This condition was in a measure dispelled by the publication in 1902 of an English translation of a little book by him entitled, "The Work of the Digestive Glands," most of which appeared in Russian during or before 1897. Up to the time of this translation, it was necessary for the reader to content himself with the French or German translation of the work or of articles from his pen in the various journals published in these languages and devoted to physiological research.

The Nobel prize would seem to have been given in the case of Pawlow more as a recognition of a long and useful service to science than for any one achievement, since it came just at the completion of the quarter-century since his graduation in medicine. In the whole of this twenty-five years, it would appear that Pawlow's activity has been unceasing, and while I am not in a position to say that the award was not