+Cold+, or the rapid abstraction of heat, is a remedial measure that is nearly always available and is possessed of very great power for good in selected cases. When cold is applied for its limited and local action, it is always used with two objects in view, namely, (1) to cause localized contraction of the blood vessels, which through inflammation are engorged, so that the parts are swollen and reddened; or (2) temporarily to anesthetize or benumb the nerve terminals, for the immediate relief of pain, in the hope that the temporary paralysis may ultimately result in such changes as to produce a cure. Cold, in some form, is a popular remedy for a sprain, or any injury likely to be followed by inflammatory processes. A very useful remedy for the sprain of an ankle, when it is a recent accident, is to let the patient sit with the foot elevated, with a cloth wrung out in ice water, and an ice bag applied over the affected part. In the treatment of localized pain or inflammation, cold is used in a number of ways, largely depending upon the will of the physician and the means of the patient. The simplest, cheapest, and perhaps the best method of using cold, is to place cracked ice in a rubber bag, the latter to be thoroughly watertight, lay it over the inflamed part, surrounding it with a towel so as to prevent the moisture, which appears on the surface from condensation, from wetting the clothing. +HEAT+ +Heat+ is used locally for a number of purposes in the same manner as cold, and the choice of heat or cold in the treatment of any acute form of inflammation depends almost entirely upon the wish of the patient, who generally can tell at once which will give him the greater comfort. In sprains of the ankle, nothing compares to a hot foot-bath prolonged for hours, the object being to decrease the pain and swelling, thereby regaining the use of the limb. The high degree of heat which can be borne by gradually increasing the temperature of the water by the addition of small quantities of scalding water, is extraordinary, and the favorable results obtained are in direct ratio to the height of the temperature. Between these soakings, the part should be dressed with lead and opium wash, and rubbed with ichthyol ointment or camphor liniment. Hot-water bottles or bags are also used locally for the relief of congestion and pain. +THE HIGH FREQUENCY CURRENT, OR VIOLET RAY+ +The Violet Ray or High Frequency Current+ is one which is in a rapid state of to-and-fro vibration and is applied through vacuum glass attachments or electrodes, which are excited to a beautiful violet color. The discharge may appear to the eye to be a single spark, but it is made up of a number of successive sparks, following each other with such extreme rapidity that they are said to oscillate (change directions) millions of times per second, a speed that the eye cannot note. The rapid oscillations have the effect of producing the following phenomena: