casts
are made of a clear, waxy, homogeneous substance (hyaline), without any
admixture of opaque particles, they imply an inflammation of longer
standing, in which the inflamed kidney tubules have been already stripped
of their cellular (epithelial) lining. If the casts are rendered opaque by
the presence of minute, spherical granular cells, like white blood
globules, it betokens active suppuration of the kidney tubes. In other
cases the casts are rendered opaque by entangled earthy granules (carbonate
of lime), or crystals of some other urinary salts. In still other cases the
casts entangle clear, refrangent globules of oil or fat, which may imply
fatty degeneration of the kidneys or injury to the spinal cord. The
presence of free pus giving a glairy, flocculent appearance to the urine is
suggestive of inflammation of the urinary pouch at the commencement of the
excretory duct (pelvis of kidney) (Pl. IX, fig. 1), especially if
complicated with gritty particles of earthy salts. This condition is known
as pyelitis. In the chronic cases swelling of the legs or along the lower
surface of chest or abdomen, or within these respective cavities, is a
common symptom. So, also, stupor or coma, or even convulsions, may
supervene from the poisonous action of urea and other waste or morbid
products retained in the blood.

_Treatment._--In the treatment of acute nephritis the first consideration
is the removal of the cause. Acrid or diuretic plants in the feed must be
removed, and what of this kind is present in the stomach or bowels may be
cleared away by a moderate dose of castor or olive oil; extensive surfaces
of inflammation that have been blistered by Spanish flies must be washed
clean with soapsuds; sprains of the back or loins must be treated by
soothing fomentations or poultices or by a fresh sheepskin with its fleshy
side applied on the loins, and the patient must be kept in a narrow stall
in which it can not turn even its head. The patient must be kept in a warm,
dry building, so that the skin may be kept active rather than the kidneys.
Warm blanketing is equally important, or even mustard poultices over the
loins will be useful. Blisters of Spanish flies, turpentine, or other agent
which may be absorbed and irritate the kidneys must be avoided. The active
fever may be checked by 15 drops tincture of aconite every four hours or by
one-third ounce of acetanilid. If pain is very acute, 1 ounce of laudanum
or 2 drams of soli