These are prescribed for application to certain parts with different degrees of friction - according to their strength, and the purpose for which they are employed. There are few medicaments more often misapplied by the amateur than popular embrocations, which unscrupulous advertisers recommend with equal confidence for a broken knee or an inflamed tendon. When used, the friction to be applied over the surface to be healed should be equally distributed, and not applied vigorously at one part and lightly at another.