f the amount
of gluten is _actually_, instead of _relatively_, increased by
peculiarities in seasons, it is no doubt correct.

I have devised a series of experiments to test the accuracy of the
statements made upon this point, but have not yet had leisure to
complete them.

_General conditions from the analyses of wheat flour_.--The large
number of analyses which I have made, and the uniformity of the
processes pursued, enable me to draw some general conclusions which
it may be useful to present in a connected form.

1. In the samples from the more northern wheat-growing States, there
seems to be little difference in the proportion of nutritive matter
that can be set down to the influence of climate. Thus, the yield of
the wheat from Michigan, Wisconsin and Iowa, is scarcely inferior to
that from New York, Indiana, and Illinois, although the two latter
are somewhat farther south. Local causes, and more especially the
peculiarities of culture and manufacture, have more influence,
within these parallels of latitude, than the difference of mean
temperature.

2. The samples from New Jersey, Lower Pennsylvania, the southern
part of Ohio, Maryland (probably Delaware), Virginia, the Carolinas,
and Georgia,[41] contain less water and more nutritive matter than
those from the States previously enumerated. That the samples from
Missouri, which is included within nearly the same parallels of
latitude as Virginia, do not exhibit so high an average of nutritive
matter as those from the latter State, must be ascribed principally
to a want of care in the management of the crop, and perhaps also in
the manufacture of the flour. Virginia flour, for obvious reasons,
maintains a high reputation for shipment.

3. The difference in the nutritive value of the various samples of
wheat depends greatly upon the variety, and mode of culture,
independently of climate. The correctness of the former statement is
shown by the much larger proportions of gluten yielded by many of
the samples of _hard_ wheat from abroad, the Oregon wheat in
Virginia, and a variety of Illinois wheat, &c. And in regard to the
effect of particular modes of culture, the various analyses of
Boussingault may be referred to, and that in my table of a sample
from Ulster county, New York.

4. The deterioration of many of