pressure is not kept just right, and the exchange of the air in the diving suit or caisson is not just right, the ear drums are disturbed and oppression, lassitude and faintness will occur, and the body is likely to become overheated. If the carbon dioxide becomes excessive of course asphyxia occurs.

Much of the danger to workmen under these conditions occurs from too rapid decompression; they must gradually come to the pressure of the outside atmosphere. If decompression from high pressure is too rapid, men suffer from severe pains, especially in the arms and legs. This has been termed "the bends." Rapid change of atmospheric pressure may cause nervous disturbances and, especially, injury to the spinal cord, perhaps followed by paralysis and coma. The cause of caisson disturbance has been shown to be due to nitrogen gas in the blood-vessels and tissues.

An insufficient amount of oxygen in a diving suit or in a caisson means suffocation, and either oxygen must be rapidly introduced in sufficient amount, or the suffocated patient must be treated for carbon dioxide poisoning, i.e., by oxygen and air, and artificial respiration.

To prevent the symptoms of decompression, the individual must be slowly decompressed, and if symptoms appear he must be again subjected to an increased compression for a short time. If serious symptoms develop, inhalations of oxygen are of value, oxygen aiding in the exchange and elimination of the extra nitrogen in the body.

DROWNING

A person who has been submerged in water more than five minutes can rarely be revived. However, even if the heart has apparently ceased to beat, artificial respiration may cause it to begin again to pulsate. The immediate treatment should be: 1. To get the water out of the lungs and stomach.

2. To begin artificial respiration.

3. To stimulate with atropine, caffeine and strychnine injections.

4. To surround the patient with dry heat, and keep him quiet and at rest.

1. To accomplish the first object, the body may be suspended for a few minutes by the heels, or it may be laid on the abdomen over a barrel or some other large, rounded object. The head should be below the chest level. The body should then be turned on the back (if the water has ceased to run out of the lungs and stomach), the nose cleaned, and the mucus removed from the mouth with the fingers and a handkerchief.

2. Artificial respiration should be immediately begun, and probably there is no better method for causing artificial respiration than the Schäfer. The patient lies prone (chest and abdomen downward, with the head turned to one side), and the operator sits at his side and makes firm pressure inwards and upwards on the body, the hands being broadly placed laterally against the region of the lower floating ribs. This pressure is exerted for three seconds, and then the body is released and the diaphragm drops, the capacity of the chest is increased, and air is sucked into the lungs. This alternate pressure and relaxation should be repeated from twelve to fourteen times a minute. If the patient begins to breathe, he may be turned on his back and his efforts aided by the Sylvester method of artificial respiration. The tongue must not be allowed to fall back over the glottis, and may either be held by tongue forceps, or a thread may be passed through it to hold it forward. While the operator is doing the artificial respiration, others should loosen the clothing, and gently, but firmly, give friction to the arms and legs, and perhaps hold the legs up, so that the blood of the body will gravitate toward the brain. If the patient starts to respire, rhythmical pulling forward of the tongue about fifteen times a minute seems to be a respiratory stimulant. The operator must be careful to coincide in his efforts at artificial respiration with the beginning efforts of the patient to respire, and not antagonize them, so that the rhythm will be synchronous. If the heart continues to beat and the patient respires at all, or artificial respiration seems to be keeping the patient alive, it should be continued until the patient either breathes freely, or the heart has ceased to beat for ten or more minutes.

3. While artificial respiration is being done, or if it has

succeeded or is not necessary, the respiratory and vasomotor centers must be stimulated, and hypodermatic injections of atropine 100 grain and strychnine 130 grain should be given immediately. If the patient can swallow, black coffee should be administered, or coffee may be administered by the rectum; or sodio-benzoate of caffeine may be given hypodermatically in 3-grain doses. Camphor may also be administered hypodermatically.

4. The body must be kept warm by friction, hot water bags, and warm blankets. Respiration and circulation having been established, the immediate subsequent treatment is absolute rest, the administration of some warm gruel or more coffee, and the continuation of dry heat. The future treatment may be that for a cardiac strain, if the patient labored severely before he succumbed; or for an insufflation pneumonia, if that develops.

BURNS

Burns are divided into three classes or degrees, depending on the depth and severity of the injury.

The primary considerations in the treatment of burns are: (1) to allay pain; (2) to protect the skin and burned tissues; (3) to prevent infection; and (4) to promote healing and repair.

While simple burns cause only slight uncomfortableness or disability, burns of considerable areas of the body may cause death sooner or later, or may cause such internal disturbances as duodenal inflammation and nephritis. When too hot air is inhaled swelling of the mucous membrane of the throat and larynx may be so great as to cause death.

In burns of the first degree where there is but slight blistering, the first treatment is to apply, freely, a solution of bicarbonate of sodium in water; or the part may be immersed in it, the water being at the temperature of the body, i.e., lukewarm. A compress wet with a 1⁄2 to 1 per cent. solution of aluminum subacetate will often relieve the local pain. Soon, in ten or fifteen minutes, the part should be gently dried and a dry powder applied, such as starch, talcum, or bismuth subcarbonate.

In burns of the second degree, where there are blisters, the same primary treatment is advisable. Later a sterilized needle

should be inserted at the outer and most pendent angles of the blisters and, by allowing the serum to gently exude, there will be relief from the painful distention. Great care should be taken not to destroy or break this epidermal layer of skin, as it makes the very best aseptic protection for the underlying inflamed skin. Sometimes the moist dressings of weak aluminum subacetate are retained in place by oil silk, but it is inadvisable to allow a poultice effect to occur. It is much better to repeatedly moisten the gauze, to prevent it from drying, rather than to allow sweating to take place. The old carron oil treatment is sedative, but may allow infection. After the first twenty-four hours there is no moist dressing better than a saturated solution of boric acid.

The burned surface should be dressed, generally, twice a day, and the shriveled, loosened or broken derm should be carefully removed with forceps, or a partially loosened piece may be cut away with scissors. Nothing promotes healing much more rapidly than exposure to the air for a short time, taking care that the part is protected by thin gauze, or other method, from infection by flies or dust.

If there is considerable destruction of epidermis in any particular area, silver foil treatment is satisfactory, it being reapplied daily where it is needed, aiming toward drying the part. If any exuberant granulations occur which prevent the skin from growing in, they should be just touched with a swab wet with a 25 per cent. nitrate of silver solution; but the proper application of silver foil will prevent the development of much exuberant granulation tissue.

Burns of any severity cause most intense and severe pain and, consequently, shock. Hence one of the primary treatments is injections of morphine with atropine, if the pain is severe. If shock has occurred, stimulation with strychnine, with suprarenal, and with caffeine may be necessary.

In the beginning of the treatment air causes the exposed skin to suffer pain, consequently exposure to air is not advisable in the early stages of these burns. Many other solutions have been advised other than the sodium bicarbonate, the aluminum subacetate, and the boric acid, but they are not more

satisfactory, and several of them (permanganate of potassium and picric acid) stain everything with which they come in

contact.

If healing is slow, continued bathing of the part with physiologic saline solution, or, if there is danger of infection or there has been much destruction of tissue, one of the Dakin solutions is advisable, and, if there is any sloughing of tissue, the part should be carefully washed with the Carrel-Dakin solution. With burns of the second degree it is sometimes necessary to do skin grafting.

During the prolonged and tedious healing of large mulitple burns, the nutrition must be carefully kept up, sleeplessness prevented, and all the functions of the body should be watched, and kept as normal as possible.

Burns of the third degree, where there is actual destruction of tissue, belong to the department of surgery, and the management of the case can only be determined by the individual conditions present. Suffice it to say, that pain must be stopped, that shock must be prevented, if possible. Some of the toxemias, and some of the shock and perhaps anaphylactic reactions caused, are due to destruction of tissues, and the absorption of protein poisons from these tissues. The suprarenal glands seem to be disturbed, hence one cause of the low circulatory tone. The heart may become disturbed, and the liver and kidneys insufficient. Severe burns are frequently more or less rapidly fatal.

The patient surviving the first twenty-four hours, the danger of infection is great, and the danger of resorption of toxins from sloughing tissues is great. The Carrel-Dakin solution used intermittently or constantly is an important aid in preventing infection and promoting reconstruction of tissues, and preventing deformities from contractions. The ultra-violet ray has been used with success for the same purpose.

The paraffin treatment of severe burns has lately been strongly advocated. Liquid paraffin is sprayed or painted over the wounds. The advantage is that it protects the burned area and seems to allow less contraction of the new tissue and therefore a better, more flexible scar. Before applying, the part