Of the Rust of Wheat.
There are several other diseases to which grain is liable, and which are much more common in this country than the ergot. But very little is known of their effects on the animal body; which circumstance, since the wheat of this and other countries often suffers from them, is probably sufficient to show that their influence must be trifling, or at all events very seldom called forth. Wheat is liable to three diseases. One is a disease of the stalk and leaf rather than of the ear, and has the effect of preventing the development of the ear or its pickles, and of covering the plant with a brown powder. Of the two other diseases, which both attack the pickles of the ear, one consists in the substitution of a brown dry powder for the farina of the pickle, and the other of a deposition of black moist matter in the fissure of the pickle, the substance of which it also invades and partially destroys. One of these is called in Scotland brown rust, the other black rust. Of the three diseases the only one which is apt to infect the flour is the black rust. The others, as they consist of a light dry powder, are almost entirely separated in thrashing and winnowing the grain. But the black rust being damp and adhesive, it is carried along with the pickles. Such pickles are almost invariably separated by the farmer if they are abundant; for otherwise, on account of the dark colour and disagreeable odour of the matter deposited on them, the flour possesses external qualities which would be at once recognized by a dealer of ordinary experience. It is not improbable, that a moderate impregnation of bread with the powder formed by the diseases in question may take place, without leading to any unpleasant effect on the human body. Experiments to this effect were made by Parmentier with one of them, termed in France carie, or caries of wheat, which from his description appears to be the black rust of of Scottish farmers. He gave two dogs each two drachms daily of the powder for fifteen days, without remarking any sign of ill health. Bread made with wheat flour containing a 64th of the powder, when eaten by various people, and Parmentier among the rest, to the amount of a pound daily for several days, caused slight headache and pain in the stomach the first day only; and in larger proportion it had as little effect.[1] It appears, then, that the introduction of any deleterious ingredient into wheat bread is hardly to be dreaded from the common diseases to which wheat is liable in this country. Of Unripe Grain.
Wheat and other grains have been supposed to acquire qualities detrimental to health, from being cut down while unripe, or used immediately after being cut down, although ripe. I am not aware that accidents have ever been traced or even imputed to such causes
- ↑ Hist. de la Soc. Roy. de Méd. i. 346.
