On Wounds of the Head — First Draft Translation

ON WOUNDS OF THE HEAD. The heads of human beings are not alike among themselves, nor do the sutures of the head grow in the same way in all people. 1 But whoever has a protrusion at the front of the head — and the protrusion is the rounded projection of the bone beyond the rest — in that person the sutures grow in the head as the letter tau, T, is written: for the shorter line grows transversely in front of the protrusion, and the other line grows lengthwise through the middle of the head, running always toward the neck. Whoever has the protrusion at the back of the head, in that person the sutures grow in the opposite arrangement from the former: for the shorter line grows transversely in front of the protrusion, and the longer line grows lengthwise through the middle of the head, running always toward the forehead. Whoever has a protrusion on both sides of the head, both front and back, in that person the sutures grow in the same way as the letter eta, H, is written; and of the lines, the long ones grow transversely in front of each of the protrusions, while the short one grows lengthwise through the middle of the head, ending at each of the long lines. Whoever has no protrusion on either side, that person has the sutures of the head as the letter chi, X, is written; and the lines grow — the one transversely, reaching toward the temple, and the other lengthwise through the middle of the head. The bone is double through the middle of the head; the hardest and densest parts of it are the uppermost, where the uniformly colored bone lies under the flesh, and the lowest, toward the meninx, where the uniformly colored bone is on the underside; and moving away from the uppermost bone and the lowest, away from the hardest and densest parts, it goes toward what is softer and less dense and more hollow, always into the diploë. The diploë is the most hollow, softest, and most sponge-channeled part. And in fact the entire bone of the head — except for a very small amount of the uppermost and lowest parts — is similar to a sponge; and the bone holds within itself what are like many soft, moist little fleshy bits, and if one were to rub them with the fingers, blood would be seen to come from them. There are also in the bone smaller, more hollow little vessels, full of blood. Such, then, is the situation regarding hardness, softness, and hollowness. In respect of thickness and thinness, of the entire head the bone is thinnest and weakest at the bregma, and the bone has the least and thinnest flesh upon it at that part of the head, and the greatest portion of the brain lies beneath that part of the head. 2 And since these things are so, given wounds and missiles equal in magnitude — and lesser ones — and when wounded alike or to a lesser degree, the bone at that part of the head is crushed and fractured more, and is driven inward, and the wounds are more deadly and harder to treat and to escape death there than anywhere else on the head; and with wounds equal and lesser, and when wounded alike or less, the person dies in a shorter time from such a wound at this part of the head than he would from a wound anywhere else, even if he is destined to die from the wound in either case. For the brain perceives most quickly and most fully at the bregma the harms occurring both in the flesh and in the bone; for the brain lies at that part under the thinnest bone and the least flesh, and the greatest mass of brain lies under the bregma. Of the other parts, that at the temples is weakest: for there is the junction of the lower jaw with the skull, and motion is present in the temple up and down as at a joint; and hearing occurs near it; and a vein, hollow and strong, runs through the temple. But the whole bone of the head from the crown and ears backward is stronger than all of the part in front, and that bone has more and deeper flesh upon it. And since these things are so, given wounds and missiles equal and alike, and even greater ones, and when wounded alike and more, the bone in that part of the head fractures and is crushed inward less; and even if the person is destined to die from the wound in any case, having the wound in the back of the head he will die in more time; for in more time the bone suppurates and suppurates through downward toward the brain, on account of the thickness of the bone, and less brain lies beneath that part of the head, and more of those wounded in the back of the head escape death, for the most part, than those wounded in the front. And in winter the person lives longer than in summer — whoever is otherwise going to die from the wound — wherever on the head the wound may be. The imprints of missiles that are sharp and lighter, when they occur on their own in the bone, without fracture and crushing, or inward compression (these occur alike both in the front of the head and in the back), from these death does not arise in the natural course of things, nor even if it does arise. 3 A suture that appears in a wound when the bone has been stripped of flesh — wherever on the head the wound may have come about — becomes the weakest thing for resisting the blow and the missile, if the missile happens to have lodged in the suture itself; and above all when the wound has occurred at the bregma, the weakest part of the head, and if the sutures happen to be around the wound, and the missile happens to have struck them. The bone in the head is wounded in the following ways; and of each way, there are several forms of fracture that arise in the wounding. 4 The bone fractures when wounded, and in the bone that contains the fracture, crushing is necessarily added alongside it, if indeed it has fractured; for whatever of the missiles fractures the bone will also crush the bone — either more intensely or less — both in the very part where it makes the fracture and in the bones surrounding the fracture. This is one way. The forms of fractures are of all kinds: some are thinner and some quite thin, so that some fractures are not visible either immediately after the wounding or in the days when it would be of more benefit to the person; while others of the fractures are broken wider and broader; and some quite wide. And some of them fracture over a longer extent, others over a shorter. And some are more straight and quite straight, others more curved and curved; and deeper downward, through the whole bone, and less deep downward and not through the whole bone. The bone might be crushed while remaining in its natural position, and no fracture might be added to the crushing in the bone. This is the second way. 5 The forms of crushing are more numerous: it is crushed more and less, and deeper and through the whole bone, and less deep and not through the whole bone, and over greater and lesser extent in length and breadth. But one cannot, having seen any of these forms with one's eyes, know what kind it is in its form, and how great in its extent; for not even whether it has been crushed or has not been crushed — the crushing having occurred and the harm having come about — becomes visible to the eyes immediately after the wounding, just as some fractures that are at a distance do not. And when the bone has fractured, the bone is driven inward from its natural position together with fractures; for otherwise it would not be driven inward: for what is driven in, breaking off and being smashed, is driven inward from the rest of the bone that remains in its natural position; and so a fracture would accompany the inward compression. This is the third way. 6 The bone is driven inward in many forms: over more of the bone and over less, more and to a deeper depth downward, and less and more superficially. And when an imprint of a missile has occurred in the bone, a fracture might be added to the imprint; and crushing is necessarily added, either more or less, if indeed a fracture is also added, in the very place where the imprint occurred and the fracture, and in the bone surrounding both the imprint and the fracture. This is the fourth way. 7 And an imprint might occur with crushing of the bone around it, while no fracture might be added to the imprint and the crushing by the missile. And the imprint of the missile occurs in the bone; it is called an imprint when, the bone remaining in its natural position, the missile having lodged in the bone makes visible the place where it rested. In each way, more forms arise; and concerning crushing and fracture — if both of these are added to the imprint, and if crushing alone comes about without fracture alongside the imprint — it has already been stated that many forms arise both of the crushing and of the fracture. The imprint itself arises on its own, being longer and shorter, more curved and more straight, and circular; and many other forms of such a way, depending on whatever the shape of the missile may be; and these themselves are also deeper downward, more and less, and narrower and wider, and quite wide. The cut: a cut of whatever length and width occurring in the bone is an imprint, if the other bones surrounding the cut remain in their natural position and are not compressed inward together with the cut out of their natural position; but if so, there would be an inward compression and no longer an imprint. The bone is wounded in another part of the head than where the person has the wound, and the bone has been stripped of flesh. This is the fifth way. 8 And this misfortune, when it occurs, you would not be able to help in any way. For even if the person has suffered this harm, there is no way that by examining him you can know whether the person has suffered this harm or where it is. Of these ways of fracture, those that call for trephining are: the crushing that is invisible to sight — and if it happens to have become visible — and the fracture that is invisible to sight, and if it is visible. 9 And if, when an imprint of the missile has occurred in the bone, fracture and crushing have been added to the imprint, and if only crushing has been added without fracture to the imprint, this too calls for trephining. The bone that has been driven inward from its natural position has little need, out of the many cases, for trephining; and those most severely compressed and most severely shattered — these have least need of trephining; nor does an imprint itself, occurring on its own without fracture and crushing, need trephining either; nor does a cut, if it is large and wide, even that: for a cut and an imprint are the same thing. First one must examine the wounded man, where on the head the wound falls, whether in the stronger parts or in the weaker, and study the hairs around the wound, whether they have been cut through by the missile and whether they went inside into the wound; and if this is the case, to declare that the bone is in danger of being stripped of flesh and of having received some harm from the missile. 10 These things, then, one must observe from a distance and state, without touching the person; then, touching him, try to know clearly whether the bone is stripped of flesh or not; and if the bone is bare to the eyes, to see it; but if not, to examine with the probe. And if you find the bone stripped of flesh and not sound from the wound, one must first make a diagnosis of what is in the bone, seeing how great the harm is and what kind of treatment it requires. One must also ask the wounded man how he was hurt and in what manner. But if it is not clear whether the bone has some harm or not, when the bone is stripped of flesh, one must all the more make inquiry — how the wound came about and in what manner; for the crushings and fractures not visible in the bone, though present there, one should first try to determine from the account of the wounded man whether the bone has suffered any of these things or has not suffered them, and then also to examine by both reasoning and examination — except by probing. For probing does not reveal whether the bone has suffered any of these injuries or has not suffered them; but probing does reveal the imprint of the missile, and whether the bone has been compressed inward from its natural position, and whether the bone has been strongly fractured — those things which are also visible to the eyes for one who looks to recognize. The bone fractures both the invisible fractures and the visible, and is crushed with the invisible crushings, and is driven inward from its own nature, most especially when one person wounds another and is wounded intentionally, or when — whether wishing to wound intentionally or acting against his will — the throw or blow is from a higher position, whichever is the greater, than from level ground; and if one grips the missile firmly with the hand, whether throwing or striking, and being stronger wounds one who is weaker. 11 Those who are wounded by falling against the bone and the bone itself — the one falling from the greatest height and onto what is hardest and most blunt, for that person there is danger of the bone's fracturing and being crushed and being driven inward from its natural position; but for the one falling more from level ground and onto what is softer, the bone suffers these things less, or would not suffer them. And of the missiles that fall upon the head and wound against the bone and the bone itself, the one falling from the greatest height and least from level ground, and simultaneously hardest and most blunt and heaviest, and least light and least sharp and soft — this would fracture the bone and crush it. And the bone is in greatest danger of suffering these things when these conditions obtain and the wound is straight-on and the bone is directly opposite the missile, whether it is struck by hand, or struck by a throw, or something falls upon it, or the person himself falls and is wounded, and however wounded with the bone having come directly opposite the missile. Missiles that glance off to the side of the bone fracture the bone less, and crush it, and drive it inward, even if the bone is stripped of flesh; for in some wounds sustained in this way the bone is not even stripped of flesh. Of the missiles, those that fracture the bone with both the visible and invisible fractures, and crush it and drive it inward from its natural position, are the round and spherical ones, with a clean striking surface, being blunt and heavy and hard; and these crush the flesh too, and make it ripe, and cut it; and the wounds that come from such missiles are undercut both to the side and in a circle, and tend more to suppuration and are moist and take longer to cleanse; for the flesh that has been crushed and cut must of necessity melt away having become pus. The oblong missiles, which are for the most part thin and sharp and light, cut the flesh more than they crush it, and likewise the bone; and they make an imprint themselves even when they cut (for a cut and an imprint are the same thing), but such missiles do not much crush the bone, nor do they fracture it, nor drive it inward from its natural position. But guided by your own visual judgment of whatever appears to you in the bone, you must also make inquiry about all these things — for these are signs of the more and less severely wounded — and whether the wounded man has been dazed, and darkness poured around him, and dizziness has gripped him, and he fell. And when the bone has happened to be stripped of flesh by the missile and the wound has happened to have occurred directly at the sutures, it becomes difficult also to identify the imprint of the missile that becomes visible in the rest of the bone — whether it is in the bone or not — and if the imprint has happened to have occurred in the sutures themselves. 12 For the suture itself, being rougher than the rest of the bone, conceals it, and it is not clear which of it is suture and which is the imprint of the missile, unless the imprint is quite large. And fracture is also added, for the most part, to the imprint occurring in the sutures, and the fracture itself also becomes more difficult to identify, the bone having fractured, for this reason: that the fracture occurs along the suture itself when it fractures, for the most part. For the bone is ready to fracture and give way there, on account of the weakness of the bone's nature in that region and on account of the looseness, and since the suture is itself ready to fracture and give way; but the other bones surrounding the suture remain unfractured, because they are stronger than the suture. And the fracture occurring along the suture is also a giving-way of the suture, and is not easy to identify — neither when it fractures and gives way under an imprint of the missile made in the suture, nor when, the bone having been crushed along the sutures, it fractures and gives way; but even more difficult to identify is the fracture arising from the crushing. For these sutures, appearing crack-like and being rougher than the rest of the bone, deceive the judgment and sight of the physician — since it has not been strongly cut through and has given way; and a cut and an imprint are the same thing. But one must, if the wound has occurred at the sutures and the missile has lodged against and into the bone, attend carefully to find out what the bone has suffered. For from missiles equal in magnitude and alike, and far lesser ones, and when wounded alike and far less, the person who received the missile at the sutures has acquired far greater harm in the bone than the one who did not receive it at the sutures. And most of these cases must be trephined; but one must not trephine the sutures themselves, but withdrawing to the neighboring bone, perform the trephination there, if you trephine. Concerning the treatment of wounds of the head, and how one must reveal the conditions occurring in the bone that are not visible, it seems to me as follows. 13 [35] A wound on the head must not be moistened with anything — not even with wine — but as little as possible; nor must one apply a poultice, nor carry out the treatment with a lint plug, nor bind up a wound on the head, unless the wound is on the forehead, in the hairless area, or around the brow and the eye. Wounds occurring in these places have more need of poultice and bandaging than anywhere else on the rest of the head. For the rest of the head entirely surrounds the forehead; and from the parts surrounding the wounds — and in whatever part the wounds are located — there is inflammation and swelling through the inflow of blood. One must not, however, apply a poultice and bandage the wounds on the forehead throughout the whole time; rather, when they have stopped being inflamed and the swelling has subsided, one must cease applying poultice and bandaging. On the rest of the head, a wound must not be plugged with lint, nor poulticed, nor bound up — except where cutting is also needed. One must cut those wounds occurring on the head — and on the forehead as well — wherever the bone is stripped bare of flesh and seems to have some damage from the missile, when the wounds are not of sufficient length and breadth for examining the bone as to what harm it has suffered from the missile, and of what kind, and how far the flesh has been contused, and what damage the bone has; and again, whether the bone is undamaged from the missile and has suffered no harm at all, and what kind of treatment the wound, the flesh, and the condition of the bone require. Such wounds, then, require cutting. And if the bone is stripped bare of flesh but the wound is hollow and extending far to one side, one must cut further into the hollow part where it is not easy for whatever medicament one uses to reach; and for round wounds that are deeply hollowed over a great extent, and the like, one must cut further and divide the circle in two lengthwise, along the natural axis of the person, so as to make the wound long. When cutting the head, the other parts of the head are safe to cut; but the temple — and even above the temple, along the vein that runs through the temple — this region must not be cut. For convulsion seizes the one who has been cut there; and if the left side of the temple is cut, the convulsion seizes the right side; and if the right side of the temple is cut, the convulsion seizes the left side. When, therefore, you are cutting a wound on the head on account of bones stripped bare of flesh, wishing to know whether the bone has suffered some harm from the missile or not, you must cut the scar to whatever size seems sufficient. 14 [45] While cutting, one must draw back the flesh from the bone where it has grown onto the meninx and onto the bone; then pack the entire wound with a lint plug, one that will provide the widest possible opening to the wound on the following day with the least pain. After packing with lint, one must use a poultice for as long a time as the lint plug is in: knead a barley-cake from fine barleymeal in vinegar, or boil it and make it as sticky as possible. On the following day, when you remove the lint plug, observe what condition the bone is in. If the wound is not clearly visible to you — what kind of injury is in the bone — and you cannot tell whether the bone has any harm in itself or not, and the missile seems to have reached the bone and damaged it, one must scrape with the scraper in depth and along the length of the person as naturally constituted — that is, head to foot — and again across the bone transversely — that is, side to side — to see the hidden fractures and the hidden contusion that has not been driven inward from the nature of the head into the rest of the bone. For scraping reveals the harm quite clearly, if these conditions in the bone are not otherwise already apparent. And if you see a seating of the missile in the bone, you must scrape both the seating itself and the bones surrounding it, lest fracture and contusion, or contusion alone, should occur in addition to the seating and then escape notice by not being apparent. After you have scraped the bone with the scraper: if the wound of the bone seems to have reached the point requiring sawing, one must saw, and one must not allow three days to pass without sawing, but must saw within these days — especially in the warm season, if you are taking up the treatment from the beginning. If you suspect that the bone is fractured, or contused, or both, reasoning from the fact that the person has been severely wounded — from the account of the wounded person, and because the one who struck was stronger (if one person was wounded by another), and that the missile with which he was wounded was one of the harmful missiles — and then that the man was seized by dizziness and darkness and was stunned and fell: when these things have occurred in this way, and you cannot tell whether the bone is fractured or contused, or both, and you cannot see it at all clearly — then one must moisten the bone with the darkest soluble wax; pack the wound with the dark melting medicament; place beneath it a linen cloth soaked in oil as a base layer; then apply the barley-cake poultice and bind it; on the following day, release it, clean out the wound, and scrape. And if the bone is not sound but is fractured and contused, the rest of the bone will appear white when scraped; but the fracture and the contusion, having absorbed the medicament — which is black — as the medicament has melted into it, will be black against the white of the rest of the bone. One must then again scrape this fracture that has appeared black, in depth; and if in scraping the fracture you scrape it away and make it disappear, then contusion of the bone has occurred — to a greater or lesser degree — which also broke off the fracture that has been made to vanish by the scraper; and it would be less dangerous and less troublesome if the fracture disappears in this way. But if it is deep and does not wish to come out when scraped, such a condition calls for sawing. 14 (50) After sawing, one must treat the remaining wound. One must be on guard that the bone not suffer any harm from the flesh, if the flesh is treated badly. 15 [20] For a bone that has been sawed, or otherwise stripped bare, whether it is sound or has some damage from the missile or seems to be sound — there is greater risk that it will become suppurated (even if it were not otherwise going to) if the flesh surrounding the bone is treated badly, and becomes inflamed, and is tightly constricted; for it becomes fevered and filled with much inflammation. And indeed the bone, from the surrounding flesh, draws into itself heat and inflammation and throbbing and beating-pulse, and all the harms that the flesh has in itself; and from these things in this way it becomes suppurated. It is also harmful for the flesh in the wound to be wet and sodden, and for it to be cleansed over a long time. But one must make the wound suppurate as quickly as possible; for in this way the parts surrounding the wound will be least inflamed and it will be cleansed most quickly; for the flesh that has been cut and contused by the missile must necessarily, once it has become suppurated, be melted away. When it has been cleansed, the wound must become drier; for in this way it would most quickly become healthy, with dry flesh growing up and not wet, and in this way the wound would not overgrow with flesh. The same account holds for the meninx around the brain; for if, after immediately sawing out the bone and removing it, you strip the meninx bare, you must make it clean as quickly as possible and dry, so that it does not become sodden and swell from being wet over a long time; for if these things happen in this way, there is risk that it will rot. A bone that must separate from the rest of the bone — when a wound has occurred on the head, and there is a seating of the missile in the bone, or the bone has been otherwise stripped bare over a great extent — separates after becoming bloodless over a large area. 16 [5] For the blood dries out from the bone both from time and from most medicaments; and it would separate most quickly if one cleansed the wound as quickly as possible and then kept both the wound and the bone dry — both the larger and the smaller part. For what has been dried out most quickly and has formed a crust — it is by this means especially that it is released from the rest of the bone that is still bloody and living; having become bloodless and dry, it is very firmly attached to what is bloody and living. As for bones that are driven inward from their natural position — being entirely broken off or cut through and very wide — such cases become less dangerous when the meninx is sound; and those that have been fractured inward with more fractures and wider ones become still less dangerous and easier to remove. 17 [15] And one must not saw any of these, nor take the risk of attempting to remove the bones, before they come up of themselves, the swelling having first relaxed. They come back up as the flesh grows up underneath; it grows up from the diploë of the bone and from the sound part, if only the upper portion has sphacelized. In this way the flesh would most quickly grow up from below and sprout, and the bones would come up, if one makes the wound suppurate as quickly as possible and renders it clean. And if both portions are driven inward through the whole bone into the meninx — both the upper portion of the bone and the lower — if one treats the wound in the same way, it will most quickly become healthy, and the bones that have been driven inward will most quickly come up. The bones of children are both thinner and softer for this reason: that they are more blood-filled, and hollow, and porous, and neither dense nor solid. 18 [15] And from missiles that are equal or weaker, and when wounded similarly or less severely, the bone of the younger child suppurates more and more quickly than that of the older, and in less time; and in whatever other ways one is going to die from the wound, the younger person perishes more quickly than the older. But one must, if the bone is stripped bare of flesh, apply one's mind and attempt to diagnose through reasoning what it is not possible to see with the eyes alone — to know whether the bone is fractured and whether it is contused, or only contused, and whether, when a seating of the missile has occurred, contusion is present in addition, or fracture, or both; and if the bone has suffered any of these things, to let out blood by boring the bone with a small trepan, taking care because the bone is thinner and shallower in the young than in the older. Whoever is going to die from wounds on the head and cannot become healthy or be saved — from these signs one must make the determination regarding the one who is going to die, and foretell what is going to be. 19 [10] For the following things happen: whenever someone fails to recognize a bone that is fractured, broken, contused, or broken in whatever way, and errs by neither scraping nor sawing when it is needed, and lets it go as though the bone were sound — fever seizes him before fourteen days for the most part in winter; in summer the fever seizes after seven days. And when this happens, the wound loses its color; a small ichor flows from it; the inflamed part has died within it; it becomes glutinous and appears like salted fish — its color reddish, somewhat livid; and the bone begins to sphacelate at that point, and becomes darkened, being white before, and finally becomes yellowish or pale white. When it is already suppurated, blisters appear on the tongue, and the patient ends in delirium. And convulsion seizes most of them on one side of the body; if the wound is on the left side of the head, the convulsion seizes the right side of the body; if the wound is on the right side of the head, the convulsion seizes the left side of the body. Some also become seized with apoplexy. And thus they perish before seven days in summer, or fourteen in winter. These signs signify in the same way both in an older wound and in a more recent one. But one must, if you recognize the fever seizing and some other sign besides occurring together with it, not delay, but saw the bone down to the meninx, or scrape it with the scraper — for it becomes easy to saw and easy to scrape — and then treat the rest in this way as seems fitting, looking to what is happening. When, upon a wound on the head of a person — whether sawed or not sawed, with the bone stripped bare — a red and erysipelas-like swelling appears on the face and in both eyes or in one of them, and if one touches the swelling there is pain, and fever seizes and shivering, but the wound itself — both the flesh and the bone — looks well upon examination, and the parts surrounding the wound are in good condition, except for the swelling on the face, and the swelling involves no other fault in the rest of the diaita — in this case one must purge the lower belly with a medicament that drives bile; and when the patient has thus been purged, the fever releases, the swelling subsides, and he becomes healthy. 20 [5] The medicament must be given with attention to the capacity of the person, according to the strength he has. Concerning sawing, whenever necessity compels one to saw a person, know it thus: if you are sawing having taken up the treatment from the beginning, you must not saw the bone through to the meninx immediately; for it is not beneficial for the meninx to be stripped bare of the bone for a long time while suffering badly — it ends up eventually becoming thoroughly sodden. 21 [35] There is also another danger, if you immediately saw through the bone down to the meninx and remove it: that you wound the meninx with the saw in the course of the work. But while sawing, when the bone needs only a very little more to be fully sawed through and it is already moving, one must stop sawing and allow the bone to separate of its own accord. For in a bone that has been sawed through and where a little of the sawing has been left, no harm could come; for what remains is already thin. The rest must be treated as seems fitting for the wound. While sawing, one must frequently draw out the saw because of the heating of the bone, and dip it in cold water. For the saw, becoming heated from its circling motion, heats the bone and dries it out, burning it, and causes a greater extent of the bone surrounding the saw-cut to separate than is going to separate otherwise. And if you wish immediately to saw through to the meninx and then remove the bone, one must likewise frequently draw out the saw and dip it in the cold water. If you are not taking up the treatment from the beginning but receive the patient from another, coming late to the treatment, you must immediately saw the bone through to the meninx with a toothed saw, frequently drawing out the saw and examining both otherwise and with the probe all around along the path of the saw. For the bone is sawed through much more quickly if you are sawing when it is already suppurated and fully suppurated, and often it happens that the bone is superficial — especially if the wound is in that part of the head where the bone happens to be thinner rather than thicker. But one must take care not to apply the saw inadvertently, but always fix the saw into that part where the bone seems thickest, examining frequently, and try to dislodge the bone by moving it, and having removed it, treat the rest as seems fitting for the wound. And if, having taken up the treatment from the beginning, you wish immediately to saw out the bone and remove it from the meninx, one must likewise frequently examine the circuit of the saw with the probe, and always fix the saw into the thickest part of the bone, and by moving it wish to remove the bone. If you are using a trepan, do not reach the meninx — if you are boring having taken up the treatment from the beginning — but leave a thin layer of bone, just as has been written for the sawing.