of the United Stales , and Territories of North America. 45 
First, Free white males under sixteen years of age. 
Secondly, Free white males of sixteen years, and upwards. 
Thirdly, Free white females of all ages. 
Fourthly » All other free persons, 
Fifthly , Male and female slaves. 
The result of this census gave a total population of 3,9 29,326. 
The next census took place in 1800, when several important 
improvements were introduced. The free white males and fe- 
males were each divided into the five following classes, viz. 
First, All those under ten years of age. 
Secondly, All those of ten, and under sixteen. 
Thirdly , All those of sixteen, and under twenty-six, including heads of families. 
Fourthly, All those of twenty-six, and under forty-five, including heads of families. 
Fifthly, All those of forty-five, and upwards, including heads of families. 
This division of the ages, although not embracing all the ob- 
jects of a perfect statistical table, must still be regarded as a 
great improvement on the objects of the former census; and it 
was a considerable step, considering the slow march of informa- 
tion on these subjects, at once to divide both males and females 
into five classes, when, in the census of 1790, the former sex 
was divided only into two classes, and the latter was taken in 
one mass, without any distinction of age. This was an advan- 
tage, because it enabled statistical enquirers to estimate the in- 
crements which each sex had received, in the different periods 
of existence afforded by the classification, and thus to institute a 
comparison with other surveys of a like kind. The classes in 
the census of 1790, relating to u other free persons,” and to 
66 slaves,” remained unaltered. The result of this census gave a 
total population of 5,309,758 persons. 
In the year 1810 another census took place ; but the classes 
into which the people were divided, and also the different sub- 
ordinate divisions, remained the same as in 1800. The result 
gave a total population of 7,239,903. 
In the census of 1820, however, the elements of some very 
important branches of statistical science were introduced ; and 
the survey assumed a milch more interesting and scientific form 
than either of the preceding. In the first place, the five classes, 
into which the free white males and females were divided in the 
enumerations for 1800 and 1810, we^e preserved ; but the free 
white males, between sixteen and eighteen, were selected from 
the class which embraced the males from sixteen to twenty-six. 
