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blood of such domestic animals as the horse, nagana or tsetse-fly disease of South Africa, the dog or ox it gives rise to a rapidly fatal except that it is caused by another species disease. The discovery that the wild ani- of trypanosome and carried from the sick mals act as a reservoir of the disease ac- to the healthy by means of another species counted for the curious fact that tsetse-fly of tsetse-fly, viz., the Glossina palpalis. disease disappears from a tract of country I now throw on the screen a map of as soon as the wild animals are killed off or Africa, showing, as far as is known up to driven away.
the present, the various fly districts, and In 1895 the living trypanosome which you will see from this map that it is not at causes the tsetse-fly disease was sent to all improbable that this human tsetse-fly England in the blood of living dogs, in disease may spread southward through the order that it might be studied in the Eng- various fly districts to the Zambesi, and lish laboratories. These trypanosomes have may even penetrate as far as the fly disbeen kept alive ever since by passage from tricts of the Transvaal and Zululand. animal to animal, and have been sent all I am sorry to say that, in spite of innuover Europe and America, so that our merable experiments directed towards the knowledge of this kind of blood parasite discovery of some method of vaccination or has rapidly grown.
inoculation against these trypanosome disKoch, in a recent address, says that our eases, nothing definite, up to the present knowledge of protozoal diseases is based on time, has been discovered. At present three great discoveries—that of the malarial there does not seem to be any likelihood parasite, by Laveran; of the Piroplasma that a serum can be prepared which will bigeminum, the cause of Texas fever or render animals immune to the tsetse-fly redwater, in cattle, by Smith; and, lastly, disease. In the same way it has also been this discovery of a trypanosome in tsetse-fly found impossible, up to the present, to so disease.
modify the virulence of the trypanosome as We may, therefore, I think, congratulate to give rise to a modified, non-fatal form of ourselves on the growth of our knowledge the disease. Again, all attempts at discovof this great stock disease during the last ering a medicine or drug which will have ten years.
the power of killing off the parasites within Since 1895 many other trypanosome dis- the animal organism, without at the same eases have been discovered in all parts of time killing the animal itself, have not as the world. The latest and most important yet been successful, although some drugs, of these is one which affects human beings, such as arsenic and certain aniline dyes and is known as “sleeping sickness.' This (Ehrlich), have a very marked effect in sleeping sickness,' which occurs on the prolonging the life of the animal. As this West Coast of Africa, particularly in the disease is fatal to almost every domestic basin of the Congo, has within the last few animal it attacks, it seems very improbable years spread eastward into Uganda, has al- that there is much chance of cultivating an ready swept off some hundreds of thousands immune race of horses, dogs or cattle which of victims, is spreading down the Nile, has will be able to withstand the action of the spread all round the shores of Lake Vic- parasite. It is quite evident that if an toria, and is still spreading southward acquired immunity of this kind could be round Lakes Albert and Albert Edward. brought about, such a race of immune aniThis disease is in all respects similar to the mals would now be found; but, as a matter
of fact, there are no horses, dogs or cattle in the 'fly country. In other protozoal diseases, such as the Piroplasmata, this acquired immunity seems to come about fairly readily.
To sum up, then, the increase in our knowledge of tsetse-fly disease during the last ten years, we may say that we have discovered the cause in the shape of the small blood parasite Trypanosoma; we have found that the reservoir of the disease exists in the wild animals, and that we can blot out this disease from any particular tract of country by the simple expedient of destroying or driving away the wild animals. We still have no means of preventive inoculation or successful medicinal treatment in this disease.
2. Trypanosomiasis of Cattle. This disease seems to be widespread over all South Africa. It can not be said to be of much practical importance, as the cattle infected do not seem to be seriously affected by it. It is caused by a species of trypanosome remarkable for its large size, which was discovered by Dr. Theiler some years ago, and named T. theileri.
Dr. Theiler states that it is conveyed from animal to animal by the common horse-fly, Hippabosca rufipes.
This, then, is a short account of the trypanosome diseases which affect South Africa.
Of late years the tsetse-fly disease has become of less practical importance to the Transvaal, from which it has practically disappeared. This is due to the disappearance of the game, killed off by rinderpest; but with the preservation and restoration of the reserves with big game the disease is certain to reappear. Why the fly should disappear with the game is not known.
D. BRUCE. (To be continued.)
EUROPEAN AND AMERICAN SCIENCE. O NE of the important accomplishments, doubtless, of the International Congress of Arts and Science held in connection with the exposition at St. Louis was, simply, the bringing to this country of a large number of learned men from other nations. Some of these men had visited America before, but many of them crossed the Atlantic last autumn for the first time and viewed Americans and American institutions with, as it were, a virgin sense. A number of those who made the trip have recorded their impressions in addresses or journal-articles. It would be a worthy task, should these increase in number, to collect and to publish them together, for aside from the gratification of the curiosity of seeing ourselves as others see us, it could scarcely fail to be instructive for us to study the observations and comments of men of the high type of those who were invited to the congress.
Of the foreign scientists who attended the St. Louis meeting and have given public expression to their ideas of America, one of the most distinguished and discerning is the professor of anatomy in the University of Berlin. It was not Professor Waldeyer's first visit to America; fond of travel and widely-travelled as he is, it was not for a man such as he to have left so long America unvisited. Moreover, an omnivorous reader, Waldeyer is more or less familiar with American literature; he numbers, too, among his friends many American scientists and literary men; indeed, many young biologists and anatomists from America have, in part at least, received their training in his laboratory. By personal observation, by correspondence, by reading and by multiple contact with educated Americans, Professor Waldeyer has had, more than most foreigners, opportunities for familiarizing himself with American science and American thought.
It must, therefore, be of especial interest to viduality, not with obtrusive ostentation, people in this country to know that he has but quietly and with that certainty which recently referred at some length to the sub- naturally accompanies the feeling of health ject of the relation of Europe (and espe- and strength; for nations are like men-he cially Germany) to American science, and who has not confidence in himself will also to learn, in brief at least, what are his soon be given up by others. He urges the views concerning it.
necessity of stilling those tendencies which Waldeyer discussed the matter in a Fest- arise from time to time in one nation to rede delivered at an open session of the unjustly threaten or injure another, the Royal Prussian Academy of Sciences in desirability of getting rid of prejudices and Berlin early this year. The occasion was of clearing up misunderstandings and unthe double celebration of the Kaiser's birth- just suspicions of the other, the importance day and the anniversary of King Fred- of directing attention in each nation to the erick II. The first part of the address good in the other, of which it is often dealt with the political relations of Ger- ignorant, owing to lack of knowledge of many and America, with especial reference the nature of the people and of their civic to Frederick's attitude toward the Amer- and social institutions. This, he points out, ican republic at its birth, a natural topic is why Germans, in order to maintain a in view of the recent presentation of the healthy and useful relation to American statue of Frederick the Great to the Amer- science, must, above all, know how the ican nation. It is the second part of the American thinks about culture and science, address which is of chief interest to the
what the present position of science and readers of SCIENCE, as it considers the
scientific investigation in America really is, special matter of the relation of Europe and how it is likely to shape itself in the and of Germany to science in America. near future. The whole address is characterized by a Waldeyer admits that in Germany the wish for harmonic relations, by a keen false opinion that the American turns predesire to foster and favor international · dominantly toward material interests and scientific intercourse and by a plea for the that he has but little inclination for purely avoidance of everything in the way of scientific things is still widespread. Those mutual misunderstanding and unseemly who hold it, he says, forget America's great discord. It is a liberal and broad-minded universities-Harvard, nearly 300 years statement, certainly as fully lenient to old, with its 5,000 students per year; Yale, America as one could ask; it can scarcely more than 200 years old; Princeton; fail to cement good feeling and to promote Brown; the University of Pennsylvania, intercontinental harmony among scientific contemporaneous in foundation with Götmen. On adverting to this special topic tingen; Columbia, established seven decades Waldeyer points out that if two peoples are ago; and young institutions, like Johns to cooperate in the work of the advancement Hopkins, Cornell, the University of Chicago of culture, the first necessity is mutual re
and the University of California, already spect between them. Each must have
grown to powerful positions in the country. something good, something self-achieved
If Germany bore in mind the great public to offer, each must preserve its own indi
libraries which exist in America, with their 1 Waldever, W., Festrede,' Sitzber. d. kg. magnificent equipment, their easy access Preuss. Akad. d. Wissensch., 1905, IV., 105-121, and their prodigious use by all classes, in
cluding the working people, such a wrong impression could not prevail. The American's recognition of the fact that culture brings freedom with it, and his realization that, in a country where every one has the choice of sinking or swimming, a good education is a necessity for him who will hold himself above water in the fierce struggle, have led to the expenditure of great sums for public schools, for advanced education of all sorts, for. museums, collections, laboratories, and the like, with results as good or better than those attained in Germany. Waldeyer, impressed with American progress in this regard formerly, confesses him self surprised at the advances made in the last decade. They surpass, he says, all expectations. “One needs no special prophetic gift to predict that, in fifty years, the United States will, as regards good arrangement, ease of use and wealth of what is offered, far outdo Germany."
Before attempting to answer the question, 'With all this liberal provision in the way of making arrangements for scientific work, has anything already been achieved in America ?' Waldeyer turns to an intermediate consideration, to a general discussion, namely, of the factors which permit and foster the development of unusual men. The relative potency of heredity and environment is considered. The basis for any special capacity, be it bodily or mental, is an inborn gift of nature; it can not be increased in a given organization beyond the limits permitted by that organization. A mathematician can not be made of a man whose brain has not the necessary endowment therefore, any more than a singer can be developed if the individual be too defective in temporal lobe, ear. or larynx. Here and there such natural capacities appear hereditarily in families, but as often or oftener the reverse appears to be the case. And it is not wealth or social
position which produces these extraordinary capacities; on the contrary, capable heads of the first rank emerge just as often from among the masses; they come from those in poor circumstances as frequently as from families that have long enjoyed conditions of preferment-an illustration of the beneficent and compensative justice of nature! That certain races are preferred can not be denied—the history of science teaches it. They are those races whose individuals, along with a healthy and harmonic development of the body as a whole, possess the largest brains relative to the body-mass. Climate, using the word in its broadest sense, here, doubtless, plays a part. Neither, the prevailing darkness of the poles nor the flood of sunlight at the equator is suitable; it is a temperate climate in countries manifoldly broken up into land and water, where the soil is fertile, and the whole gamut of seasons is run through, which must be designated as most favorable. In such a climate men must work, but the work rewards and strengthens. Not that this climatic factor. works directly; rather its action is such that it gives rise to strong, healthy men with superior brains. On the other hand, it is just as true that culture already attained and institutions of favorable influence already established, such as superior schools, well-organized and liberally endowed libraries and provision for the interchange of mental products, often help to permit intellectually important men to appear. As of two equally well-organized muscles, that becomes more efficient which is given the opportunity to exercise and test itself; so of two equivalent brains, the one which is offered the more abundant and better intellectual nourishment and the greater opportunity for exercise will yield the higher product. Many a highly endowed head has failed to become fully active, owing to
the existence of barriers to its development. state does not trouble itself about religious Great geniuses like Napoleon I., Shake- creeds, nor these about the state. All this speare and Gauss may, it is true, overcome affords a wide horizon and creates a feeling every obstacle; by virtue of their extraor of personal independence-a feeling which dinary creative power they can do without Americans inherit from the founders of and still not be held back; but easily access the republic and which is traditionally ible aids will undoubtedly awaken to able maintained in their bringing-up. performances men of capacity, who other. The magnificent equipment of America's wise would slumber.
scientific institutions reflects the national On comparing ‘old Europe' with the character. High praise is accorded by United States Waldeyer points out that the Waldeyer to the Smithsonian Institution, 'climatic' factor is in both instances all from which so many foreigners have rethat can be desired. Though in western ceived favors; to the Washington Academy North America there are wide areas less of Sciences, with its various subdivisions; favorably situated, a vast proportion of to the American Association for the Adthe country is as favorably located and vancement of Science, and to the National formed as any part of Europe. The type Educational Association. But as a bioloof man is the same, indeed the whole of gist, the Berlin anatomist is best able to Europe has sent, in large part, of its best judge of the state of the biological sciences to contribute to the population of the here. After referring to his personally United States. The means of culture are repeated conviction of the advances making the same; in many respects America has in America he says: “I find that over there the advantage, especially as regards ease they stand equal to us in all essential points, of use and multiplicity of institutions. in the kind and method of scientific work, There can be no doubt, then, that in Amer- in the value of the same, in the equipment ica effective men and women must develop and arrangement of laboratories, in main all spheres. Waldeyer calls the atten- terials for instruction and in the form and tion of his countrymen to the fact that it mode of imparting knowledge. Visit the is by no means, as some think, in the nat- great workshop of Alexander Agassiz in ural sciences and technical subjects that Cambridge; the anatomical institutes of Americans have already distinguished Huntington in New York, at Columbia themselves; he cites, in evidence, a list of University, and of Mall in Baltimore; the naturalists, economists, jurists, philologists, Peabody Museum, so brilliantly filled by philosophers and historians of the first Marsh, at Yale; the anthropological murank.
- seum in New York, etc., and you will say Some of the reasons for German failure that I am right. J. Orth has recently made to comprehend Americans are made clear. a similar statement. In a few years the To understand the people of the United new buildings of the Medical School at States properly, one must, he emphasizes, Harvard will be ready; * * * it may be keep in view the fact that even their oldest prophesied that in them we shall have the towns never had walls, that there have best to be seen anywhere." never been feuds between cities, nor strug- In view of the present standing and gles between lords and men, that compul. promise for the future of science in Amersory service and burdens other than those ica, Waldeyer, proceeding with his address, self-imposed are unheard of, and that the urges the maintenance and strengthening