There is a paper out there by Liam Brunt which contains an
argument on agricultural productivity in England between 1700 and
1850 which fits rather nicely with Clark's 1991 findings. Brunt
calculates that, between 1705 and 1775, *output per worker*
almost doubled, but "thereafter labour productivity was fairly static".
He also says that English *output per acre* increased by 70%
between between 1705 and 1775, and that, thereafter,"the value of
output per acre continued to rise strongly in England (58% higher
by 1845)".
Why labor productivity or output per worker did not continue to
increase after 1775, whereas land productivity or output per acre
did? First, we should be aware of Brunt's definition of labor
productivity - which is similar to that of other researchers
including Clark - as a "function of both the local acres per worker
and the local output per acre". Land productivity, however, is
estimated as a function of crop output per unit (i.e. acre) of land.
So, we can have a situation in which crop output per acre
continued to increase but not labor productivity, because additional
units of labor time were required to raise output per acre.
And this is in fact what happened after 1770. When we examine
the factors responsible for the continued increase of land
productivity after 1770, we find that they were labor intensive
factors such as the widespread adoption of turnips and clover, land
drainage, as well as liming and marling of the land. Adding turnips
to the crop rotation, for example, required a lot of labor through
hoeing and lifting....In this respect, I disagree with Clark's
conclusion that there was no agricultural revolution in the period
between 1750-70 and 1850. The revolution started after 1600, but it
did not stop after 1770.
