among its millions of industrial policy holders, supplemented with the development of nursing care for those acutely ill; and the death rate during this period dropped about one-third in ten years. With this drop in the death rate, there was an increase of eight and one-half years in the expectation at birth for these insured lives representing the working population of America.

It will thus be seen that the mortality rate and the corresponding average after-life time respond very quickly and favorably to intelligent effort. However, we are still far from having obtained the maximum possibilities in the extension of human life under present conditions, in even the country with the best record, in any group among whom the experiment has yet been tried.

As to the future (says Dublin), it would be futile to prognosticate on the basis of any substantial future advances in medical, surgical or sanitary knowledge, though certainly important advances will be made within a short time.

"The most important single item of mortality is the record for the first year of life. Fifteen per cent. of all the deaths that occur each year are of children within the first year of age. Infant mortality cuts heavily into the life expectation because a death in that year erases the entire expectation for that life, whereas a death at say forty or sixty, removes only relatively few years of life; hence the effect in the average is slight. Fortunately, there is compensation for high infant mortality: its relative ease of prevention and control. In the registered area of the United States the infant mortality in 1921 dropped to 76 per 1,000

births. In New Zealand it was below 50; and some cities in the United States were below 40.

Dublin assumes for his hypothetical life table an infant mortality rate of 38.2 per 1,000-an entirely realizable figure. This leans, he holds, to the side of conservatism; because it has been already realized in a number of places. This figure can be surpassed if the suppression of infant mortality for the first month can be made possible; and it can, for very little has yet been done. The detection of syphilis in the mother, the control of the toxemias of pregnancy, and the securing of good obstetrics for the great body of parturient women, coupled with adequate nursing will accomplish much to improve figures for the first months of life.

Infant mortality rates of 20 per 1,000 and even below are on the horizon.

Likewise the mortality rates for the succeeding second, third, fourth and fifth years of childhood are materially reducible. The figures assumed by Dublin vary between 34 and 40 per cent. of the actual mortality rates for the respective ages in 1910. He has assumed a mortality rate of 4.2 per 1,000 for the third year of life. In New Zealand, nearly fifteen years ago, the rate was 5.3.

In the third year of life about two-thirds of the entire mortality is due to such infections as typhoid, diarrhea, enteritis, measles, scarlet fever, whooping cough, diphtheria, tuberculosis and the respiratory diseases. And these diseases are now within control, provided we mean to control them. For example, diphtheria is almost within reach of eradication by means of the wholesale inoculation of children with toxin-antitoxin.

Between the age of ten and sixty, Dublin assumes that mortality can be reduced to one-half the 1910 figure. This is only twenty per cent. less than New Zealand; in that country, however, there is still much preventable mortality from tuberculosis, during that fifty-year period as well as from accidents and occupational diseases. In the later years of this period there is much preventable arterio-cardio-renal disease.

Insurance companies can do much by arranging for annual physical examinations of their policyholders and the hygienic follow-up work by which the insured persons bring their impairments under medical supervision. Ordinary policy-holders in the Metropolitan Life who availed themselves of the Life Extension examinations over five years ago showed at the end of the period a mortality 28 per cent. lower than that of the best control group the company could muster.

Success in handling tuberculosis gives rise to optimism. Since 1911 the disease has declined 50 per cent. in the Metropolitan and almost as much in progressive cities. The peak or maximum rate by age is constantly being pushed forward into the later years of life, thus extending the expectation.

Per contra death rates from heart disease, Bright's, cerebral hemorrhage and other diseases affecting mid-life are not declining. These represent heavy loss to the community, since they involve so many people in their prime and at their height of usefulness. Heart disease, Bright's and cerebral hemorrhage alone curtail expectation about four years. Reductions of acute infections like typhoid, diphtheria, and acute rheumatism which

are so likely to damage heart, kidneys, and vascular systems in young people as well as extension of health education, will eventually assist in reducing the mortality in these degenerative diseases of a later period.

Life-saving campaigns in industry will materially help. Excessive heat, dust, contact with poisonous substances, occupational accidents; all these can be mitigated.

Dublin has made no allowance for any possible saving from cancer, or in the saving of life after the age of seventy. There may be some improvement in the rates in both these categories.

Dublin's hypothetical life table compared with the expectation prevailing in registered areas in the United States, indicates a gain of ten years at birth; five and one-half years at 20; three and a quarter years at 40; two and one-half years at 50; one and one-third years at 60; at 70 and after, no gain. The total death rate would be reduced from 13.0 to 8.6 per 1,000, assuming no change in the age constitution of the present population. So that an extension of the expectation by ten years would be accomplished by coincident reduction in the death rate of 33.8 per cent.

On the new life table basis, there would be a total of close to 916,000 deaths in the United States as against a total of nearly 1,379,000 which occurred in 1920-a saving of 463,000 lives a year.

A reduction of the infant mortality to a third as assumed, means the saving of 126,000 infants a year. There would be a saving of 171,000 children in the first five years of life.

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