Popular Science Monthly/Volume 84/April 1914/The Progress of Science
MORTALITY STATISTICS OF THE UNITED STATES
The Bureau of the Census has published its thirteenth annual report on mortality statistics, this report for 1912 following closely on that for 1911. The death rate in the registration area, which now includes about two thirds of the population, fell from 14.2 for each thousand of the population in 1911 to 13.9 in 1912. There are always fluctuations in the death rate due to weather conditions, epidemics, etc., but, as shown in the chart taken from the report, the death rate has steadily decreased from 17.6 in 1900. This means that in so short a period the saving of human lives in this country amounts to about 350,000 a year, a statement which it is difficult to appreciate at its true magnitude. In 1880 the death rate was 19.8. If we
Late Hollis Professor of Mathematics and Natural philosophy in Harvard University, distinguished for his contributions to mathematical physics.
put a merely commercial valuation on the lives saved, it amounts to a billion dollars a year. It would surely be reasonable to spend the amount thus saved by better living conditions, improved hygiene and more efficient medical service to promote further advances in the same direction.
The death rate has declined in all the great nations, with the possible exception of Russia and Japan. Thus since 1886 the decrease in England has been about 6, in Germany about 9, in France about 3. These great differences for different nations are in large measure due to the age constitution of their populations. Thus England has doubled its population by natural increase in sixty years and Prussia in fifty years, but now the birth rate is rapidly declining. There is thus in their populations a small proportion of old people and a decreasing proportion of young children, which in large measure explains why the death rate is lower than in France where the population has been nearly stationary and there are nearly twice as many old people. The death rate for New York City in 1912 was 14.5, and for the entire state 15, but this does not mean that conditions are more favorable to health and to long
life in the city than in the country. The death rate in New York City is low because owing to emigration from abroad and the influx of young people from the country an unusually large percentage of the population is at the age when deaths are few.
In order to compare populations of different age and sex constitutions it is necessary to recalculate the rates for a standard population. Our Census Bureau has rather oddly chosen the population of England as the permanent basis of standardized rates. This population is about as abnormal as could be found, it having resulted from a large birth rate rapidly declining and a large emigration. For example, there is an excess of 1,200,000 women. There should be an international convention to fix a standard population, either a weighted average of the populations of the countries having adequate statistics, or an ideal population resulting,
The Magnetic Work of the Department of Terrestrial Magnetism, showing the ocean cruises and land stations.
say, from a birth rate of 20 and a death rate of 15.
The curves that are reproduced showing the death rates for each hundred thousand of the population from certain diseases can not be very accurate, as it is in many cases impossible to assign a single cause for death, and the returns of physicians are incorrect in a large percentage, perhaps in a majority, of cases. Still the curves are instructive, more especially in showing the decrease in certain contagious and preventable diseases, and the increase in certain organic diseases. In the short period of eleven years the rate for tuberculosis has decreased from 202 to 149; for infant diarrhœa, from 109 to 70; for typhoid fever, from 36 to 16; for diphtheria, from 43 to 18. On the other hand, the rate for heart disease has increased from 123 to 151; for apoplexy, from 67 to 75; for Bright 's disease from 89 to 103, and for cancer, from 63 to 77.
It is evident that people must die some time and somehow; if they escape from the diseases prevalent in the earlier years of life, they must die from those of later life. It is also the case that the decreases noted are far greater than the increases. Still it is true that the decrease in the death rate is in the earlier age groups, while there has been an increase after the age of fifty-five. This has been attributed to the fact that the conditions of modern life are unfavorable to people of middle age. The fact seems to be, however, that the diseases from which people are likely to die in middle and old age are not to a considerable degree preventable, and the very fact that the lives of millions of infants and young people who were below the average in constitutional strength have been saved must lead to a higher death rate when they become more advanced in years.
THE WORK IN TERRESTRIAL MAGNETISM OF THE CARNEGIE INSTITUTION
Among the large mass of important scientific research conducted under the auspices of the Carnegie Institution of Washington and described in the annual report of the president, that in terrestrial magnetism deserves special notice this year, in view of the fact that it is being provided with a permanent laboratory. As the director of the department, Dr. L. A. Bauer, points out, work on terrestrial magnetism and atmospheric electricity has been mainly observational. Magnetic and electric surveys have been extended to nearly all parts of the earth, and observatories have been conducted at a number of points at which are registered the variations to which the magnetic and electrical elements are subject with time and with varying planetary and solar conditions. But hitherto there has been no laboratory for the investigation of these phenomena of terrestrial and cosmical physics similar to the laboratories of astrophysics, to which are due such remarkable progress in that science.
The Carnegie Institution, which in the establishment of the solar observatory at Mount Wilson has contributed very greatly to the advance of astrophysics, has now undertaken to construct for its work in terrestrial magnetism the building of which views are here reproduced. It is being erected on a tract of land of about seven acres in Washington, about a mile north of the Bureau of Standards and the Geophysical Laboratory. The grounds are sufficiently removed from disturbing influences, so that the testing and comparisons of magnetic instruments and work in atmospheric electricity may be successfully carried on. The building, which is now nearly completed, consists of a basement, two stories, and an observation-roof, the size being 51 by 102 feet.
In addition to the work done in Washington, magnetic surveys of land areas have been made in various parts of the earth, including the Sahara Desert, Canada, west of Hudson Bay, northeastern South America and Australia. The accompanying map shows how extensive have been these surveys, including the two cruises of the non-magnetic ship Carnegie, which has now traversed a distance of about one hundred thousand miles, preceded by cruises of some sixty thousand miles by the chartered ship Galilee.
The Carnegie Institution has, in addition to this new laboratory and its administration building in Washington, erected buildings for its departments, each with their equipment, valued as follows: The Solar Observatory on Mount Wilson and at Pasadena, $754,000; the Geophysical Laboratory in Washington, $198,000; the Desert Laboratory at Tucson, Arizona, $48,000; the department of Experimental Evolution at Cold Spring Harbor, Long Island, $70,000; the Nutrition Laboratory, adjacent to the Harvard Medical School in Boston, $129,000, and the Department of Marine Biology at the Tortugas, $47,000. This last laboratory it is now proposed to remove to Jamaica.
SCIENTIFIC ITEMS
We record with regret the death of Dr. Robert Kennedy Duncan, director of the Mellon Institute for Industrial Research in the University of Pittsburgh; of Professor William Whitman Bailey, professor emeritus of botany at Brown University; of Dr. Roswell Park, professor of surgery at the University of Buffalo; of Edward Singleton Holden, librarian of the U. S. Military Academy, formerly director of the Lick Observatory; of Dr. Albert Gunther, late keeper of zoology in the British Museum, and of Sir John Murray, the distinguished oceanographer.
Sir Francis Darwin delivered the first Galton anniversary lecture on February 16 in London. The subject of the lecture was Francis Galton—Professor R. W. Wood, of the Johns Hopkins University, gave in London, on February 27, the first Guthrie lecture of the Physical Society, his subject being "Radiation of Gas Molecules Excited by Light."