If, during the progress and various changes of disease, it should assume different appearances, first of the healthy, and then the opposite aspect, the case is doubtful, and danger may be apprehended; as it affords sufficient demonstration, there is a powerful struggle in the system, and the morbid miasma is not subdued. The best state of a horse's urine, when in HEALTH and CONDITION, is of a yellowish tinge, moderate consistence, a strong smell, rather grateful than offensive, and a penetrating property: these, in the aggregate, may be concluded indications of _spirits_, _strength_, and _vigour_; the reverse, (in any serious degree,) slight symptoms of disquietude, or impending disease. After all the inculcations that can possibly be introduced under this head, the most judicious and experienced practitioner will sometimes find it extremely difficult to distinguish, with certainty, between one internal disease and another; having nothing to assist him in the discovery but his own judgment, and the most predominant symptoms at the _moment_, many of which are common to other diseases. Notwithstanding these uncertainties, and the doubts which may arise between one and the other, it is the duty of every Veterinarian to acquire as perfect a knowledge as possible of DIAGNOSTICS; for although his incessant inquiries may not render him an _infallible_ guide in every case without exception, it will afford him the gratification of a distinguished superiority over those who have neglected to avail themselves of the same advantages.
SINEWS—is the fashionable and common term for the tendinous coat of the muscles extending from the back of a horse's knee to the fetlock joint, when which is in any degree elongated by _strain_, _twist_, or any other accident, the horse is then said to be broken down in the BACK SINEWS. The sinews or tendons are liable at all times to violent spasmodic contractions (see CRAMP) not only in any one of the extremities, but throughout the whole body; the immediate and remote causes of which are hitherto undiscovered, and will most probably remain so, in respect to _certainty_; although there are not wanting speculators of _mental fertility_, who attribute them to various causes, without having, perhaps, in the whole number, fixed upon the _right_. One class of these _suppose_, convulsive contractions of the tendons are occasioned by _surfeits_, or the want of proper evacuation; another, from too plentiful and repeated bleedings, too violent purgings, or too hard labour; assigning for a reason, "that these fill the _hollowness_ of the SINEWS with cold windy vapours, which are the only great causes of convulsions." Where they occur from accidental causes, and casual injuries, as in wounds, perforations, or instrumental incisions, the origin is obvious, and in a certain degree points out the immediate road to local relief. When a tendon has been in part divided, or only punctured, a succession of painful and most alarming symptoms invariably ensue, and relief can only be obtained by early application to the best opinion, and most experienced judgment, that can be produced; with the very slender and mortifying consolation, that not one in twenty (if severely injured) ever after proves of any permanent utility.