membrane begins in white patches, especially at the junction of the mucous membrane and the skin. By friction and movement these patches develop into sores, yet chancre in the corner of the mouth is not unknown, and is followed by enlargement of the cervical lymphatics similar to bubo.

The treatment of a case like this should be mercurial. But in what form? Some writers recommend the chloride. It is a good remedy in chronic cases, but in my experience is slower than calomel. The protiodide is also good, but, of late, I rely more upon calomel than upon any other compound of mercury.

I now show you the child. Here are macula and condylomatous patches about the anus. One patch is above the skin. There are dark maculæ on the legs, and, as I shall show you, also on the rump. Here is a very distinct mucous patch on the vulva, and here are others; also the remains of chancres, as well as small vegetations on the labia. Finally, there are condylomata of mild type in each corner of the mouth.

I propose to give the child two grains of calomel daily, that is, one grain twice a day, combined with opium to prevent action of the mercury on the bowels. The condylomata, by the aid of dryness and powdered calomel, will get well. When they are large and moist, I use chromic or nitric acid. But in those which are thin and flat, dryness. and the calomel powder answer every purpose. How far should the internal treatment be pushed? Until the gums are slightly spongy and the breath has the mercurial odor. When this condition is reached I shall reduce the calomel to one grain daily. In those instances in which the mouth becomes sore before we know it, a mouth wash of the chlorate of potash is needed. Under this treatment the child's skin and mucous membrane will probably clear up and get well.

In the hereditary syphilis of children, to give mercury by inunction is a good treatment, but care is necessary, because the mercury is sometimes absorbed very quickly. Rub the ointment into localities in which the skin is thin, as the armpits and groins.

Necrosis. Our second case is that of a boy too young to give us his history, and there is no older person to do it for him. What is to be thought of this leg? In what does it differ from the left? Is it larger or smaller? Is it softer or harder? It is larger and harder than the other, and this is due to enlargement of the bone. What bone? The tibia, as we can see by bending the knee. Here is an open sore with pouting lips situated near the head of the tibia; also several scars, some of which are dimpled. A dimpled scar is caused by adherence of the skin to the bone, and is a sign that the sore, of which it is the cicatrix, penetrated to the periosteum and probably involved the bone. On passing my probe into the open sore, I find that it enters some distance into the shaft of the bone, thus showing an affection of the medullary

cavity. What is the character of the disease? Is it caries or necrosis? The child is scrofulous, and has scars and open sores. Caries is more apt to affect the extremities of bones, and is often due to low forms of inflammation. At any rate it prefers the extremities and the cancellated structure of bones. If I should cut down through the sore into the cancellous tissue and find a spongy, yellow cavity, filled with broken fat cells and blood, and so soft that it could be broken up with a probe, I could go on indefinitely digging away the softened bone. Such a condition of disease is caries or ulceration of bone, but such treatment is of no use, because we do not dispose of all the disease. It is like scraping off the surface of an ulcer and expecting it to heal at once from the bottom. Nature has not set a limit to the diseased process, but if there be reason to believe that pus is burrowing, we should give it a free outlet. In necrosis it is necessary to remove the sequestrum, if by gouging down we can find it. We thus get rid of a foreign body and stop the inflammation.

The symptoms here make me suspicious of caries, and especially the location of the open sore. But other symptoms are significant of necrosis, so that I am equally balanced between the two affections. Our best procedure will be to cut down and enlarge the opening into the bone. I should also call your attention to the weakness of the knee-joint, which bends outward, showing a lack of strength in the internal lateral ligament. In the other knee we find no such weakness.

This is an instructive case, not because it is rare, but because it is an ordinary, every-day case, and we meet so many like it. Our diagnosis is to be decided by operative interference, which will discover the true nature of the affection. To prevent undue hæmorrhage I will first apply the Esmarch bandage from the toes up to the thigh. Introducing my probe I find it fairly in a cavity. This is an indication of caries, and, as you notice, the diseased point is near the head of the bone. But the disease has been lower down, as shown by the scars. It will now be proper to make a crucial incision, and see if we can find anything within. You will observe my probe going down into the cavity. With my dressing forceps I tear away the débris, and within the cavity find. dirty pus and a rough, hard bottom. This is unlike caries, and is prob ably necrosis. My probe goes quite a distance downward, but not upward. I think it proper to enlarge the opening into the bone. It is shaped like a bullet hole. By means of mallet and chisel I cut out a piece of bone, which I finally loosen and bring away with the bone forceps. This reveals the sequestrum, which, being quite large, will require further enlargement of the opening. I thus succeed in removing one large mass, which, practically, is a slough of bone. Beyond the site of the sequestrum the cavity seems closed. Nothing else remains than exfoliated fragments, and the bottom of the cavity is hard.

and bounded by firm bone. I cannot say too much in favor of the Esmarch bandage, which has given us the opportunity to explore the bone without any hæmorrhage. As I remove the bandage you see the blush of the returning circulation as it comes down the leg, showing how perfect it is. Now we see an oozing of blood in the wound. How shall we arrest this hæmorrhage? By packing the bone cavity with small sponges. But I first put into the cavity a square of oiled cloth. When I take out the sponges, one by one, I shall have no difficulty, and shall cause no pain, because of the oiled rag. I now insert the cloth, pack in the sponges, and bandage over all. In twenty-four hours I shall remove the sponges and dress with antiseptic appliances, and keep the patient in bed. This will be the whole treatment. In six weeks the cure will probably be established.

Compound Fracture. I finally have to show you a man who has just been brought into the hospital for treatment. While at work the point of a pickaxe in some way was driven entirely through his left hand, near the ulnar border. The result is a lacerated wound and a compound, comminuted fracture. The fifth metacarpal bone has been cut through. But I do not feel justified in treating or examining this case without ether.

In administering ether to patients who are fully dressed, we should be careful to see that there is no interference with the action of the diaphragm. Loosen the waistband and whatever there may be about the neck. This man has a leather strap about his waist, and this we remove. In females the corsets should be unfastened and the strings which hold the skirts untied. Otherwise the diaphragm will not have the free play which is vitally necessary, because after etherization we depend upon this muscle. When the patient has become insensible he sinks down in the chair, and still further impedes a diaphragm which may be already constricted by garments. If we have to turn an etherize patient upon his side, to examine the rectum, for instance, we must take care that the arm, which in this position is drawn back, does not become dislocated. Drawing back the arm causes the patient to fall forward, and makes it easier to examine or introduce a speculum into the rectum or vagina. One cannot be too careful, however, to keep the shoulders elevated; otherwise the movements of the thorax are interfered with, or the patient's face might fall into the pillow and he become suffocated.

I now examine our patient freely, and find that the injury is very ragged. The fourth metacarpal bone is all right, but the fifth has been so cut that a large piece is gone or has been driven down into the wound. The fracture is rough and comminuted. The upper fragment points upward and the lower downward and backward. The perios teum is mostly gone, and the missing bone cannot be renewed because of this loss of periosteum.

The best treatment will be to saw off the rough ends of the bone, remove all fragments, and afterward syringe out the opening daily with antiseptics; and, to promote suppuration, apply a flaxseed poultice mixed with charcoal to keep it sweet. Thus we treat the hurt as an open wound. In all lacerated and punctured wounds it is worse than useless to close them by stitches.

A CASE OF THIRD DENTITION.

BY EDWARD J. FORSTER, M. D.,

Surgeon to the Charlestown Free Dispensary and Hospital.

THE history of the case from which the cast represented in the annexed wood-cut was taken is as follows:

occupied is shown on the cast by the roughened line to the left of the tooth now present.

C. A. Harris, in his Dental Surgery, quotes from Good's Study of Medicine, as follows: -

"For the most part, the teeth in this case (third dentition) shoot forth irregularly, few in number, and without proper fangs, and even where fangs are produced without a renewal of sockets. Hence, they are often loose, and frequently more injurious than useful by interfering with the uniform line of indurated and callous gums, which, for many years perhaps, had been employed as a substitute for the teeth."1 The tooth shown in the wood-cut made its appearance four years ago, and is serviceable, although the owner thinks it is "beginning to rot" and is afraid he will soon lose it.

In regard to the possibility of a third dentition, Harris says:

The Principles and Practice of Dental Surgery. By C. A. Harris, M. D., D. D. S., etc. Eighth edition, p. 176.

"That nature makes an effort to produce a third set of teeth is a fact which, however much it may be disputed, is now so well established that no room is left for cavil or doubt."

Wedl, in his Pathology of the Teeth, gives the names of eleven writers of recent times who have either seen or reported cases, but expresses no opinion as to his own belief, saying, "The possibility of the occurrence of a third dentition is doubted, and even openly denied by many." The cast which was kindly made for me by Edward Page, D. M. D., has been deposited in the Warren Museum of Harvard University.

THE VOLUMETRIC METHOD OF WRITING PRESCRIPTIONS.

BY W. H. LATHROP, A. M., M. D., TEWKSBURY, MASS.

In a recent article upon the metric system, Dr. T. B. Curtis very justly observes that the question of measuring as opposed to the weighing of liquids is one entirely distinct from the decimal system of weights and measures. I am strongly of the opinion, however, that the physician in prescribing liquids, whatever be the system employed, should use the volumetric rather than the gravimetric method. It seems to me that this whole question turns upon the method in which a preparation is to be administered. It being admitted that the medicine will be given out at the bedside by measure, should not the prescription be so written as to show how much it will measure? It is a question whether it is the business of a physician so to acquaint himself with specific gravities that he can express these measures in weight. What does a physician gain by such a mode of expression? Suppose, for instance, that it is desired that a patient shall have a solution of chloral in syrup, of the strength of one gramme of chloral to ten cubic centimetres of the solution. The physician directs, we will say, that the patient take five cc. at each dose, knowing that in this way exactly half a gramme of the active medicine will be received. Such a prescription, I am confident, would be in no way improved by translating the cubic centimetres to their equivalent in grammes.

When the liquids of a prescription are expressed in volume the physician can look over it and tell at once how many doses of each active ingredient it contains, and if the decimal system is used this is especially easy. Suppose that laudanum is to be prescribed in the dose of one cubic centimetre (sixteen minims), while five cc. is to be the dose of the prescription. If the liquids are expressed volumetrically the physician has only to observe that his tincture comprises one fifth of his whole prescription to make sure that the opiate appears in proper quantity. Here is exactness with celerity. Gravimetric expression, on the 1 Translation from German, by W. E. Boardman, M. D., Philadelphia, 1872, p. 87.