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 the samples of wheat and wheat flour arises in most cases from the presence of a too large per centage of water.  This is often the result of a want of proper care in the transport, and is the principal cause of the losses which are sustained by those who are engaged in this branch of business.

5.  There seems to be little doubt that a considerable portion of the wheat and wheat flour, as well as of other breadstuffs, shipped from this country to England, is more or less injured before it reaches that market.  It is also shown that this is mostly to be ascribed to the want of care above noticed, and to the fraudulent mixture of good and bad kinds.  The remedy in the former case is the drying of the grain or flour before shipment, by some of the modes proposed, and the protection of it afterwards as completely as possible