w Jersey from 1790 to 1860,
compared with that of Maryland, is still greater than that of
Massachusetts. The law is inflexible wherever slavery disappears.
Population of New Jersey in 1790, 184,139, in 1860, 672,035, being an
increase of 264 per cent. (264.96) for New Jersey, of 225 per cent.
(225.06) for Massachusetts, and for Maryland 114 percent. (114.88). The
ratio of increase per square mile from 1790 to 1860 was: Massachusetts,
48.55 in 1790, and 157.82 in 1860; Maryland, 28.74 in 1790, and 61.76 in
1860; and New Jersey, 22.01 in 1790, and 80.70 in 1860. Thus, while
Maryland from 1790 to 1860, little more than doubled her ratio of
increase per square mile (28.74 to 61.76), and Massachusetts little more
than tripled her ratio (48.55 to 157.82), New Jersey very nearly
_quadrupled_ hers (22.01 to 80.70). It must be conceded, however, that
the natural advantages of New Jersey are far greater than those of
Massachusetts, whose material and intellectual progress, in defiance of
such serious obstacles, now is, and most probably forever will be,
_without a parallel_. Now the area of New Jersey is but 8,320 square
miles; the soil of Maryland is far more fertile, the hydraulic power
much greater, the shoreline much more than double, viz.: 531 for New
Jersey, to 1,336 for Maryland; while New Jersey, with rich iron mines,
has no coal, and one third of her area is south of the celebrated Mason
and Dixon's line, the northern boundary of Maryland. While the Free
States have accomplished these miracles of progress, they have peopled
eleven vast Territories (soon by subdivision to become many more
States), immigration to which has been almost exclusively from the North
as compared with the South.

The Slave State which has increased _most_ rapidly to the square mile of
all of them from 1790 to 1860, has had a smaller augmentation per square
mile than that Free State which has increased most _slowly_ per square
mile during the same time of all the Free States, and the result is the
same as to wealth and education also. Under the _best_ circumstances for
the Slave States, and the _worst_ for the Free States, this result
proves the uniformity of the rule (like the great law of gravitation),
knowing no exception to the effect of slavery in depressing the progress
of States in population, wealth, and education.

The isothermals of the great Humboldt (differing so widely from
parallels), which trace the lines of temperature on the eart