626 THE POPULAR SCIENCE MONTHLY. 



In 18C9 a table taking a far wider range was compiled, known as 

 "Actuaries' Experience Table No. 2." It comprised the experience of 

 twenty English and Scotch offices, all over twenty years old. It treats 

 of 146,847 lives, which on an average had been under observation for 

 ten years, and records 23,856 deaths. This table was not graduated 

 until recently, and is only beginning to come into use. 



About the same time Mr. Sheppard Homans published the " Ameri- 

 can Experience Table," based principally on twenty-six years' experi- 

 ence of the Mutual Life Insurance Company of New York. For the 

 very young and old ages where the data were insufficient^ he also made 

 use of other American and English statistics. This table has been 

 adopted as the official standard for New York and many other States. 



The exact numbers and other details that served as a foundation 

 for all these mortality tables have been given rather fully, at the risk 

 of wearying the reader. The object has been to indicate the difficul- 

 ties of obtaining them in a reliable and sufficient form, and on such a 

 scale as to furnish trustworthy averages. 



A little reflection will show that large numbers must be observed 

 -for a long term of years, to have deaths occur for every single year of 

 life, and in the proper proportion for each age. Take as an illustra- 

 tion the Carlisle table based upon 1,840 deaths in eight years, which 

 would average 230 deaths per year. According to the present mor- 

 tality of England, about forty per cent, of the deaths of the whole 

 population occur among children under five years old, forty per cent, 

 between the ages of five and sixty-five, and twenty-per cent, in old 

 age, between sixty-five and one hundred years. Apply these percent- 

 ages to the 230 deaths at Carlisle, and they would give 92 persons 

 dying under five years old, 92 between five and sixty-five years, and 

 46 between sixty-five and one hundred years of age. For the last 

 thirty-five years of life only 46 deaths would be likely to take place, 

 because, while the percentage of mortality is high, the number living 

 at those ages is very small. But, when 46 deaths are distributed 

 among thirty-five years of life, it is apparent that they are not likely 

 to prove regularly divided among them. At some ages, and they may 

 be the very highest, no deaths at all may occur. We know, however, 

 that it is not in the course of nature that in any one year of life no 

 human being should die, and properly ascribe it to the small number 

 and the short space of time observed. Here the mathematician steps 

 in and determines, from the insufficient data gathered, what the prob- 

 able percentage of deaths would be for every year of life, in large 

 communities living under similar conditions. 



In illustration of what has been said, and as both interesting and 

 instructive, the actual percentage of deaths comprised under the " Un- 

 graduated Actuaries' Experience Table No. 2" is herewith given in 

 graphic representation: 



The table shows the remarkable fact that, out of so large a number 



