=Nephritis= is not so common at the present time as it used to be formerly; the growing information of the people has in some measure altered the practices of the stable. The master is not quite so much the slave of a groom's ignorance as was once universally the case; the animal is no longer regarded as a mysterious creature which it required a particular education to understand. Urine balls, therefore, are no longer regularly kept in every loft. Niter--one ounce of "_sweet_ nitre," or, to speak correctly, an overdose of _harsh_ saltpeter--may, however, be still permitted, and by particular horse proprietors regarded as a charm against every ill. It is true that such a dose of a powerful diuretic is four times the strength which science would, under any circumstances, approve; but certain people in remote parts are happy in the conviction that an ounce of "_sweet_ niter" can _possibly_ do no harm. The urinary organs of the horse must be little disposed to disease; they must be capable of surmounting a vast quantity of ill treatment. Were not ignorance thereby protected from the consequences which it provokes, half the horses in England would be disabled; inflammation of the kidneys would become the most common of equine disorders. The horse has small need of diuretic medicine; it is much exposed in that direction. Every purge, should it not act as intended, passes out of the body by stimulating the kidneys; the ordinary provender of the animal may operate in the same manner. Foxy oats, kiln-dried oats, new oats; musty hay, mow-burnt hay, new hay; beans in particular conditions; grasses, when first in season, and water of any novel kind, will all operate energetically upon the renal glands; therefore the horse, in its ordinary food, will possibly imbibe more than a sufficiency of a most debilitating medicine; and the knowledge of such a liability may induce some men to withhold "_sweet_ niter" from the future diet of the creature. It may be necessary to inform men and masters that a horse needs rest when under the operation of diuretic, quite as much as when subject to the action of purgative medicine. It is never safe to take the horse from the stable while the animal is passing any unusual amount of water. Excess of secretion proves the eliminating organs are excited. Before any part can exhibit excitement, an extra quantity of blood must circulate within it, or it must be in a condition bordering upon inflammation. The urine is secreted from the blood by the kidneys; therefore before a greater bulk of water can be passed, of course more blood must flow through the glands.