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
