36 Mr. Worcester on Longevity. 
tion from the old states to the new. Among the emigrants 
there is a large proportion of the young and active, and but a 
small one of those advanced in life. This circumstance tends to 
increase the proportion of the aged in the old states, and to 
diminish it in the new. 
Qdly. Difference in the ratio of inerease of population. In 
newly settled countries, where every man may easily obtain the 
means of living in as good a style as that of his neighbours, ear- 
ly marriages are almost universal. Of course the number of 
births, provided the country is tolerably healthy, greatly exceeds 
that of deaths, sometimes in the ratio of three or four to one. 
Those, therefore, in the early stages of life, will, in these circum- 
stances, bear an uncommonly great proportion to those drawing 
near its close. : 
3dly. Difference of climate. It is to this cause that the 
differences observable in such of the old states as increase in 
nearly an equal ratio, is chiefly to be ascribed. But it is owing 
principally to the two former reasons, that in the newly settled 
states, there is found so great a proportion of the population un- 
der the age of 10 years, and so small a proportion upwards of 
45. In addition to these there are other causes, of a moral nature, 
of more or less influence, arising from the difference in the condi- 
tion and habits of the people in the several states. 
Dr. Dwight, in his “Travels” [see Vol. I. Letter VI.], has given 
a view of the comparative healthiness of New England and some of 
the Southern States ; and comes to the conclusion that the chance 
of living to the age of 45 in Connecticut, is to the chance in 
Georgia, as2to 1. That the chance of living to this age in Con- 
necticut, is greater than in Georgia, is doubtless true ; but the differ- 
ence is by no means so great as stated by Dr. Dwight. Indeed it 
