rengthened the tendency of migrating planters to stay within
the cotton latitudes. Many of those who settled about Baton Rouge and on
the Red River with cotton as their initial concern shifted to sugar at the
end of the 'twenties, however, in response to the tariff of 1828 which
heightened sugar prices at a time when the cotton market was depressed.
This was in response, also, to the introduction of ribbon cane which
matured earlier than the previously used Malabar and Otaheite varieties and
could accordingly be grown in a somewhat higher latitude.

The territorial spread was mainly responsible for the sudden advance of the
number of sugar estates from 308 operating in 1827, estimated as employing
21,000 able-bodied slaves and having a gross value of $34,000,000, to 691
plantations in 1830,[42] with some 36,000 working slaves and a gross value
of $50,000,000. At this time the output was at the rate of about 75,000
hogsheads containing 1,000 pounds of sugar each, together with some forty
or fifty gallons of molasses per hogshead as a by-product. Louisiana was at
this time supplying about half of the whole country's consumption of sugar
and bade fair to meet the whole demand ere long.[43] The reduction of
protective tariff rates, coming simultaneously with a rise of cotton
prices, then checked the spread of the sugar industry, and the substitution
of steam engines for horse power in grinding the cane caused some
consolidation of estates. In 1842 accordingly, when the slaves numbered
50,740 and the sugar crop filled 140,000 hogsheads, the plantations were
but 668.[44] The raising of the tariff anew in that year increased the
plantations to 762 in 1845 and they reached their maximum number of 1,536
in 1849, when more than half of their mills were driven by steam[45] and
their slaves numbered probably somewhat more than a hundred thousand of
all ages.[46] Thereafter the recovery of the cotton market from the severe
depression of the early 'forties caused a strong advance in slave prices
which again checked the sugar spread, while the introduction of vacuum pans
and other improvements in apparatus[47] promoted further consolidations.
The number of estates accordingly diminished to 1,298 in 1859, on 987 of
which the mills were steam driven, and on 52 of which the extraction and
evaporation of the sugar was done by one sort or another of the newly
invented devices. The gross number of slaves in the sugar parishes was
nearly doubl