often fair room for question whether the recovery might not equally have taken place without the operation. I must here remark that I limit these observations to gunshot fracture with depression, as an opposite opinion appears to be deducible from the recorded experience of trephining in similar injuries as occasioned by accidents in civil life."

Some surgeons, also, do not employ the trephine in any description of cases of injury of the cranium, but advocate leaving everything to nature, except taking away any loose pieces of bone or foreign body that can be removed without injury to the brain; and this seems to be the practice generally pursued amongst army surgeons of the present day.

VI. OPERATION OF TREPHINING.

The scalp is to be divided by a circular or a V incision, or the wound may be enlarged in any suitable or convenient manner,then the central pin of the trephine is to be protruded about the eighth of an inch, and well fixed and firmly placed on the external table, and with a sharp, light, rotatory movement of the hand the teeth should be carried into the bone. The external table and diploe may be quickly divided; the central pin should be withdrawn lest it perforate the bone first and injure the dura mater. Greater caution is required as the instrument approaches the vitreous table, or where the thickness of the bone is irregular, or where the diploe is almost wanting. The saw must be very lightly and cautiously used and taken out, the teeth cleaned, and the groove examined with the flat end of a probe or a quill to ascertain that it is of the same depth all round. When the bone is loose it may come away with the trephine, or the elevator is to be employed to raise the loosened portion. A circular piece of bone is taken away in this manner in cases of purulent collections, or extravasation of blood, or a foreign body in the cranium. A little more than a semicircular portion of bone should be removed in cases of depressed fractures; the central pin should be fixed on the margin of the sound bone, as the object of taking away a semicircular piece only is to allow of the introduction of the elevator to raise the depressed portion of

bone. It is sometimes necessary to trephine at the frontal sinuses, when the external table should be removed with a trephine of larger size, so that the internal table may be more easily reached. Hay's saw is sometimes very useful in removing portions of bone. The scalp should be replaced, sutures if necessary inserted, and cold water applied, and antiphlogistic measures adopted to avert inflammation of the brain and its membranes, or of the veins in the diploes or in the sinuses, which may suppurate and quickly prove fatal.

The opening made in the skull by the trephine is filled up by the same process as takes place in the formation of new bone in other parts of the osseous system; the pericranium, dura mater, and bone all assisting in it. The aperture in the skull is filled up, either entirely or only in part, according as the pericranium and dura mater are injured, the age of the patient, and the size of the hole; plastic matter is thrown out, filling up the opening, which becomes cartilaginous, and in which granules of new osseous matter is deposited chiefly around the margin. The aperture never becomes perfectly firm and the same as the rest of the skull, whatever may be the age of the patients, and in some cases the opening requires to be protected by a piece of leather or some kind of elastic cap.

VII. HERNIA CEREBRI.

Hernia, or protrusion of the brain, takes place in cases of compound and comminuted fractures with laceration of the cerebral substance. It sometimes projects through the aperture, becomes strangulated, and sloughs, and generally terminates fatally from inflammation; or it may project and undergo the same process without, in some cases, any material derangement to the cerebral functions.

When a deficiency of the cranium exists, whether caused by the use of the trephine or not, precautions ought to be taken to prevent hernia of the brain by steady and uniform pressure, and by strict antiphlogistic measures. When a hernial protrusion has actually taken place, steady and firm compression and bandaging are the best means of cure.

When sloughing occurs it may, on some occasions, be admissible to use the knife, but escharotics should not be employed. The protruded part in true hernia of the brain is formed of disorganized cerebral substance mixed with blood and lymph. On some occasions a coagula projects, with a thin coating of brain, which resembles the true hernia cerebri.

Out of eleven cases recorded in the Museum Catalogue where the trephine was employed, seven were followed by hernia of the brain, and out of these seven, two recovered; as cases of fungus or hernia of the brain, see J. Evans, J. Collins, and T. Cain, at pages 16, 39, and 47, etc., and also the following.

No. 3481.-Drawing showing gunshot wound of the head.— It shows exceedingly well the appearance of a fungous tumour arising from the brain; it was cured by pressure in fifteen days. Private Thomas Deverill, æt. 24, 61st Regiment. Fracture of right parietal bone, with depression. Was hit with a musket ball on the 13th January, 1849, at Chillianwallah, which caused a small wound in the scalp and fracture of the right parietal bone near its anterior and inferior angle; the wound was dressed with adhesive plaster. 16th.-A T incision was made to see the state of the fracture and as a means of abstracting blood. 3xvj were allowed to flow from the wound. The bone was found to be very much depressed and comminuted. About 4 o'clock, p.m., he was more drowsy, and on being roused he appeared morose, and complained of the same kind of pain and intolerance of light. The operation of trephining was had recourse to; the head of the trephine was placed more than half above the fracture, and a circular piece of bone was removed. The dura mater and middle meningeal artery were wounded by the depressed bone, and the artery poured out bright, scarlet-coloured blood in a continuous stream, ascending seven or eight.inches; it was restrained by pressure of the fingers. Three loose portions of bone were taken away, and the depressed portion elevated to nearly the same level as the surrounding. The operation being finished, the meningeal artery was allowed to bleed to the extent of 3xij. The lips of the wound were brought together, and slight pressure with a pad and bandage was used. He went to bed without assistance, and expressed himself free from pain or headache. 31st.-Within

the last two days a fungous tumour has sprung from the situation of the wound in the dura mater, and is now almost the size of a hazel-nut, of a bright, pink colour, and pulsating; it is diminished by pressure without causing any pain or uneasiness, but on pressure being removed, returns to its former size. 15th.-Wound healed; sent home for change of climate, as India would be too hot for a person who had lost such a large portion of bones of the head.

VIII. ABSCESSES OF THE LIVER CONSEQUENT ON Gunshot WOUNDS OF THE HEAD.

Abscesses of the liver resulting from injuries of the cranium have been thought to be of frequent occurrence, more especially in those which suppurate than from simple concussion. Sometimes after a severe shock no abscess forms in the liver; at other times abscesses are found where no shock has been received. They are also occasionally observed in cases of diseased brain arising from other causes.

In many cases of injury of the cranium neither the liver nor any other organ sympathises; in others almost every organ suffers. There may be only slight pain in the region of the liver, torpor, or bilious diarrhoea, or some other evidence of functional disturbance, to the actual formation of abscesses in the liver; they are most frequently deep-seated, and of very large size; sometimes, however, they are superficial, and they may either point externally, or burst into the lung, stomach, or colon. The abscesses are of a very chronic character, and form without almost any general disturbance; at other times there are symptoms of acute inflammation. Injuries of the head very frequently occur to people under the influence of liquor and to those of intemperate habits generally, where the liver is otherwise disordered, and are thus rendered more susceptible to disease. On the other hand, they are observed in those of abstemious habits.

The stomach also suffers from sympathetic nervous influence, vomiting and irritability of the stomach being frequently observed where no diseased appearance is discoverable on dissection. The spleen is likewise disturbed by the shock in injuries of the head,

also the thoracic viscera; increased secretion taking place in the serous cavities, with the formation of abscesses in the structure of the different organs. Priapism and loss of the sexual powers has also been observed in injuries of the cranium.

IX. TREATMEnt of GunsHOT INJURIES OF THE HEAD.

The treatment of concussion and compression has already been described.

All cases where inflammation of the brain or its membranes is to be dreaded after removing its cause, should be treated on the strictest antiphlogistic principle; bleeding from the arm, leeches to the head, opening the temporal artery or jugular vein, shaving the head, and applying ice or other cold lotion, such as this,-composed of 4 ozs. of nitrate of potash, 2 ozs. of muriate of ammonia, 1 pint of vinegar, and 10 pints of water. With regard to the mode of dressing in gunshot wounds of the head, a piece of fine wet linen is first applied, which adheres to the wound, and should not be frequently removed. Over this Stromeyer recommends that a net, made for the purpose, should be placed, so as to retain the dressing, and the cold applications are to be made through the net. Patients labouring under wounds of the head are frequently so restless that the wet lint is quickly tossed off, so that the suggestion of Stromeyer appears to be worthy of being generally adopted. Internally purgatives, calomel until it begins to affect the mouth, given in two-grain doses every four or five hours according to circumstances, and mercurial ointment rubbed into the thighs so as quickly to affect the system; at a late period blisters to the head or to the nape of the neck, and also a seton, should be the means employed, according as the case may require.