Post-mortem examination.—The chest was contracted; the ribs unyielding, with extensive adhesions of the pleurae. Both lungs were of a dark-blue colour, much puckered from patches of false exudation. There was extensive effusion into both cavities of the chest; and the right lung showed carbonaceous infiltration throughout its whole extent. The superior lobe was excavated, so as to contain a small orange; and about six ounces of thick, black matter were found in it. The middle lobe was crepitant, though soaked with black fluid; several impacted lobules were scattered throughout its substance. The inferior lobe was indurated, resembling a piece of moist peat. The left lung was cavernous in both lobes, and the cysts were empty, the contents having been expectorated. A small portion of the upper lobe was pervious to air. There were several enlarged bronchial glands at the root of both lungs; and the tracheal glands contained black fluid. The liver was large, and its substance soft.

Head.—There was extensive congestion of the blood-vessels of the brain, with effusion into the lateral ventricles. The viscera of the abdomen were extensively congested, with slight effusion into the peritoneal cavity.

It will be observed in referring to the history of this case, that till the time this man became a stone-miner, and carried on his operations with the aid of gunpowder, he had no symptom of the disease of which he died, and it is evident that the disease, if commenced at all, had made little or no progress till after his return from Penston colliery to Pencaitland, and after he had inhaled the residuum of gunpowder combustion, therefore the disorganization of the pulmonary structure was to all appearance effected between the summer of 1836 and December 1838, showing decidedly the very irritating character of gunpowder smoke upon the delicate tissue of the air-passages.

CASE 9. J. D., aged 37, at his death, April 1844. He was a well formed man, with a fully developed chest. At so early an age as seven years, he engaged in the labour of the coal-pit at Preston-Hall, Mid-Lothian, and he continued to prosecute that employment for a period of 15 years, when he was obliged to relinquish the work on account of an affection of the chest, being, as he termed it, "touched in the breath." During the subsequent 15 years of his life, he had never once entered a coal-pit, nor had he any connexion with coal-works, but earned his bread by the trade of a travelling merchant. He had suffered much in his wanderings, from his breathing,[15] for more than two years continuously, while loss of appetite, and thoracic irritation, had rendered his physical frame as weak as that of a child.

When I first saw this man, which was about a month before his death, he laboured under rending cough, with a scanty tough mucous expectoration—oppressive dyspnoea, ascites, general anasarca, occasional giddiness, and throbbing headach on motion, or on assuming the standing position. His countenance was of a light blue or slate colour, and his upper and lower extremities had much the same appearance. His lips, eyelids, ears, and nose, were swollen and livid, and his eye-balls effused, and apparently projecting from the sockets. His sight was impaired and hazy. There was continued feeling of cold, with occasional rigors, and difficulty in keeping the extremities warm. There was considerable exhaustion upon the slightest exertion. The half reclining posture was the only one in which he was comfortable. The pulse was exceedingly slow, not above 36 in the minute, it was small, and often imperceptible at the wrist. There was considerable weight and feeling of oppressive fulness in the region of the heart, which was dull on percussion. On applying the ear to the chest, little or no rale whatever was discernible, and the action of the heart was almost inaudible. He had a sensation as of great weight in the head, and difficulty in raising it. Ho suffered from restless nights, short hurried breathing, with a feeling and dread of suffocation, evident fulness and enlargement in the region of liver, and inability to turn to the right side. The urine was small in quantity, of a bluish colour, and coagulable, irritability of stomach, and the bowels were obstinate and difficult to move, even with drastic purgatives. The treatment was merely palliative, no stimulant seemed to have any effect in exciting the system. Ascites and general anasarca were considerable, giving the body a large appearance. For some days previous to his dissolution, there was increased lividity of countenance, and little or no action of heart. He had at no time expectorated carbon, even during many severe paroxysms of cough. Upon inquiry, I found that this man had been a companion in labour to R. R. (whose case No. 2, is fully reported,) at Preston-Hall colliery, and from the morbid appearances found in R.'s chest, and from the character of the coal-work in which both were engaged, I was induced to believe Duncan's to be a similar case. In ascertaining his early history, I found him to be a robust powerful man, though troubled with a cough and hurried breathing from his first becoming a collier, circumstances very usual with those who engage in difficult mining operations, and which they erroneously attribute to want of air, nothing more.

Post-mortem examination, twenty-four hours after death.—The body was much swollen from effusion. On removing the anterior part of the chest, both lungs were much compressed from an immense effusion of a light brown fluid into the cavities of the chest to the extent of a gallon. The lungs were of a deep black colour, and irregularly spotted with dark brown patches of exudation. There were considerable adhesions of the pleurae, and marks of very general chronic inflammation and false membrane over the greater part of the pleura costalis. There were adhesions of the left lung to the pericardium, which was much thickened, and contained about 14 ounces of a turbid fluid. On removing the left lung, it seemed large, and felt partially consolidated, and on dividing it throughout both lobes, it contained a mass of semi-fluid carbon, of a bright black colour, similar to paint. In this lung, the air-cells were almost entirely disorganized, unfitting it for the function of respiration. The upper lobe was divided into a variety of cysts, filled with carbonaceous matter in a fluid state, into which many of the smaller bronchi opened, and through which various blood-vessels passed uninjured. The inferior lobe, when emptied of its contents, was so much excavated that the parenchymatous substance felt light and flaccid. On dividing the right lung[16] it exhibited a pure black mass, but not so fully disorganized as the left. Portions of each lobe were permeable to air, while other parts formed cysts, containing fluid and solid carbon, the inferior lobe showed an almost solid mass. The mucous membrane of the respiratory passages was inflamed and spongy throughout the divisions, the small ramifications were irritated and choked up with tough, frothy phlegm. There were several large bronchial glands at the root of the left lung. In tracing the divisions of the bronchi more minutely, from the root of the lungs into their substance, clusters of glands were observed filled with inky fluid, and narrowing considerably the air-passages, and in washing carefully a portion of the upper lobe of the right lung, and removing as far as possible the carbonaceous matter, several lymphatic glands were seen with the aid of the magnifier, imbedded in the interlobular cellular tissue, resembling small black beads. The tracheal glands when examined, contained black fluid, similar in appearance to what was found in the bronchial glands. The mucous membrane of the trachea was soft and irritated, smeared with tough bloody mucus, the lining membrane of the rima glottidis was thickened and slightly granular.

The heart was much enlarged, and soft, with spots indicating chronic inflammatory action on and about the right auricle. Both auricle and ventricle on the left side of the heart contained a deep-dark blood. There were several large lymphatic glands imbedded around the great vessels proceeding from the base of the heart, containing black fluid, the other cavities appeared healthy, though attenuated in substance. The coronary veins were congested. None of the cervical glands contained black fluid, though several of them were enlarged. The cavity of the abdomen much distended from ascites; the contained fluid was to the extent of about six Scotch pints of a straw colour; the viscera much compressed, and matted together, with light brown exudation. The peritoneum was rough, and coated with the same exudation. The stomach and all the intestines correspondingly contracted; the mesentery appeared healthy; the liver was much enlarged, and darker than usual; the inferior lobe extending downwards, near to crest of ileum; the whole organ loaded with inky-coloured blood; the substance easily torn. The kidneys presented a natural appearance; the adipose substance in which they were imbedded was oedematous; the medullary substance of each presented a yellowish colour.

Head.—The integuments were oedematous. On exposing membranes, considerable effusion under arachnoid; very general venous congestion, extending over the convolutions, and to the base of the brain. Effusion into the lateral ventricles of a light yellow; the choroid plexuses thickened, and of a dark venous appearance; substance of brain firm and apparently healthy.

From the history of this case, it will be found that D. had at no time shown any indication that carbon was infiltrated into the lungs. At an early age he came under the influence of the smoke of coarse linseed oil, and of gunpowder, while labouring in an unhealthy and ill-ventilated pit, which produced a cough common amongst colliers, who may be placed in similar circumstances; and it is evident, that during the last fifteen years of his life, the carbon—having previously taken up a lodgment in the pulmonary tissue—was gradually accumulating, and thereby producing painful dyspnoea, and the other formidable symptoms connected with the circulating organs, which followed as results, till it had almost entirely saturated the cellular structure, and rendered the lungs unfit for the functions of respiration, consequently impeding the necessary change, through the medium of that function upon the blood.

There was a marked similarity in the morbid appearances between this case and that of Reid, (No. 2). They both wrought in the same pit at Preston-Hall, and were affected in a similar manner. Both had enlarged liver, and the left lung principally disorganised. Both had extensive anasarcous and other effusions, and both had coagulable urine. Neither expectorated black matter, and both died from the bursting of a carbonaceous cyst into the bronchi, producing suffocation. Duncan lived longer under the infiltration than Reid did; and this was no doubt owing to his being younger, and also his healthy occupation latterly.

I have preserved a quantity of the contents of a cyst in the left lung of this patient, for chemical analysis; also a portion of the blood from the vena cava, and a little of the black fluid from the bronchial glands.[17]

CASE 10. (The subject of the following case is still alive, 1845.) J. S., aged thirty-six. He was born of collier parents, in the parish of Pencaitland, and at as early an age as eight years, went under ground to assist his parents in the transmission of the coal, and when fit for work became a coal-hewer. From his infancy he was rather of a delicate constitution, with flat and contracted chest. When I first saw him, which was about eight years ago, (1837), he was in full employment as a coal-hewer, complaining of shooting pains through his chest, tickling cough in the morning, with scanty tough expectoration, and frequent palpitations. He was repeatedly under treatment for bronchial affection, which was usually relieved by expectorants, blisters, and continued counter-irritants. Each attack of bronchitis was the result, as he expressed it, of "breathing bad air in the pit," in which he was obliged to relinquish labouring, as the lamp would not burn, from the state of the atmosphere. He never wrought at the stone-mining nor blasting. In examining the chest with the ear, at this stage of the affection, the mucous rale was distinctly heard, and exceedingly loud throughout the greater part of the chest. The heart's action was strong, but natural; pulse 70, full and bounding. About four years ago, he removed from Huntlaw to Blindwell, a coal-work towards the sea-coast, an extension of the same coal formation. At this time, 1841, he had very troublesome cough, particularly in bed, scanty frothy expectoration, annoying dyspnoea, preventing him taking sufficient nourishment, headach, obstinate bowels. He continued under all these ailments to labour with much difficulty, till the summer of 1843.[18]

In reviewing the morbid appearances in the cases now detailed, it will be observed, that in the majority of them, the left lung exhibited the greater amount of diseased structure. This fact is particularly interesting, as in tubercular phthisis, a similar predominance of disease is found on the left side.

In almost all the cases, there was found very extensive effusion into the serous cavities, and particularly into those of the pleura and pericardium. Both pleurae were much thickened, and all the marks of a long standing pleuritic and pericardial inflammatory action were seen. The substance of the heart, in all the cases, was soft and attenuated; the right auricle and ventricle were dilated; and there was thickening of several of the valves. The liver and spleen were usually large and congested. In all the cases, as the disease advanced, the pulse came down to a very unfrequent and thready beat. From the great extent of the venous congestion, the disease often assumed the aspect of asphyxia; and in some instances the colour of the patients resembled that of persons labouring under cyanosis.

The lividity of countenance, and the other concomitant symptoms, which presented themselves, gave decided indications of the morbid effects of this extraneous body. It requires little explanation to show how such a diseased state of the pulmonary organs, as has been described, should produce such results, by impeding the necessary chemical change of the blood. Imperfect oxygenation of the blood, consequent on the altered pulmonary structure, must cause a general depression of all the vital organs. The excess of excrementitious matter in the circulation, must produce effusion of serum into the various cavities, and also into the cellular structure; and the appearances exhibited on the surface of the brain and its membranes, afford a full explanation of the sluggish inanimate condition of all the sufferers towards the close of their existence.

From the cases above reported, it must be evident, that black phthisis is the result of foreign matter inhaled and retained within the pulmonary structure.

It is a melancholy fact connected with mining occupations in the locality described, that few or none who engage in it, escape this remarkable disease. I have never known one collier in many hundreds, who, even in his usual health, was not, as he expressed it, more or less "touched in his breathing;" and after much experience in auscultation in such pulmonary affections, I am the more convinced that the dyspnoea from which they suffer, arises from impaction of the minute bronchial ramifications induced during their labour below ground, surrounded by an impure atmosphere. The East Lothian colliers, of all miners throughout the kingdom, are certainly most subject to this disease; and those at Pencaitland are so to a fearful extent. In the late inquiry for the Parliamentary report, such has been manifestly brought out, and I am quite able to corroborate the conclusions at which the commissioners have arrived. It has been supposed by many that this carbonaceous affection was caused by inhalation of coal-dust. Now, when it can be proved, that there is as much coal-dust at one coal-work as at another, the question comes to be, why should colliers, labouring at one coal-work, be subject to the disease; while those engaged at another, escape? For instance, there is as much coal-dust at Penston and Huntlaw, where there has never been black spit, as there is at Pencaitland, Preston-Hall, and Blindwells. I conclude, therefore, that this cannot be the cause, otherwise they should all be liable to the disease. Again, those who labour as coal-bankers at the mouth of the shaft, are obliged to inhale much coal-dust in shovelling and arranging the coal received from the pit, and have the sputum tinged to a certain extent by it—which resumes its natural appearance when the collier leaves the labour producing it. They are not subject to the miners' cough, nor is there carbonaceous infiltration found in the lungs of such labourers after death. The females and boys, when, as formerly, both were allowed to labour, could not fail to inhale much of the coal-dust in which they were generally enveloped in their daily occupation; but no carbonaceous deposit has ever been found in the pulmonary tissue of either the one or the other. There are very interesting facts connected with the history of this disease, showing the length of time which the carbon can be retained, brought out by two cases on record, the one published as formerly mentioned by Dr James Gregory, in the Edinburgh Med. and Surg. Journal for 1831, denominated, "Spurious Melanosis;" the other, a case published by Dr William Thomson, (Medico-Chirurgical Transactions of London for 1837), and which was reported to him by Dr Simpson, now Professor of Midwifery in Edinburgh.

Dr Gregory's case is that of John Hogg, who had been in the army for more than twenty years, had seen much service as a soldier in America and the West Indies, and had served in Spain during the Peninsular war. On his return to his native country, he was engaged for a short time before his death as a collier at Dalkeith. I understand, upon inquiry, from those who were connected with Hogg, that he wrought in early life as a miner at Pencaitland coal-work, and was obliged, though a young man, to relinquish such employment on account of a chest affection, and exchange the pick for the musket. From the history of this case, and from the character of his occupation in early life, I apprehend that the carbonaceous deposit took place when he was first labouring as a miner at Pencaitland; and that he carried the foreign body in his lungs, throughout his campaigns.

The case reported to Dr Thomson by Dr Simpson is that of a George Hogg, who lived at Collinshiel, near Bathgate. In early life, this man laboured at Pencaitland coal-work, where the greater number of the cases now under consideration occurred; and it is stated as a certainty, that he contracted the black phthisis while occupied in that district; for I find from those who knew him at an early period, that his breathing was much affected while at Pencaitland, and he was long supposed by his fellow-miners to have imbibed the disease,—indeed he removed from Pencaitland on account of it. The two Hoggs were relatives, and natives of East Lothian.

It is evident, from several of the cases, that it is no uncommon feature of this affection for the carbon to remain concealed in the pulmonary tissue for very many years; and as both the Hoggs were miners at Pencaitland, I have not the smallest doubt that it was then and there that the disease had its origin; for I have never known a collier who was a stone-miner who did not ultimately die of the carbonaceous infiltration.

Apart from colliers and coal-mines, as a proof that carbonaceous particles floating in the atmosphere are inhaled and lodged in the bronchial ramifications, I may state the following circumstance, which came under my own observation several years ago. After a gale of wind, which had continued for more than a week, off the coast of America, in the July of 1832, I was applied to for advice by several of the seamen, on account of a tickling cough, followed by a peculiarly dark blue expectoration, which I was told was almost general amongst the crew. I was certainly at a loss, and put to my shifts, to render a reason; but, upon investigating the matter further, I found that, during the gale, the chimney of the cook's apartment in the 'tween-decks was rendered inefficient, whereby the sleeping-berths were constantly filled with smoke. I found almost all the seamen, to the number of nearly a hundred, suffering considerably from cough, and expectorating an inky-coloured phlegm, which continued more or less for about a fortnight. I ordered soothing expectorants, and the dark sputa were profusely voided, and ultimately disappeared; but whether any of the carbon had made a permanent lodgment in the pulmonary tissue, is what I have never been able to ascertain. I am now convinced, in recalling this occurrence, that whatever be the situation, should carbon be floating in the air, it can be conveyed into the air-cells; and had these seamen been longer subjected to this foul atmosphere, a permanent lodgment of the carbon would undoubtedly have been the consequence, and the disease now under our consideration to a certainty produced. I further remember seeing, several years ago, a case of partially carbonized lungs in a person who had lived for a length of time in a smoky and confined room in Glasgow. The patient died of dropsy, consequent, no doubt, on the pulmonary affection; and on examining the chest, the upper lobe of both lungs, and the bronchial glands contained black matter, similar in appearance to that found in the colliers.

While engaged in committing these remarks to paper, I have been led in my investigations to compare the various kinds of labour carried on in coal-pits with the underground operations of many of the railways now in progress throughout the kingdom; and being convinced of the very injurious effects produced upon miners while prosecuting these operations in confined situations where gunpowder is used, I shall be much surprised if the same results do not follow the hazardous undertakings connected with railway tunnelling, where gunpowder is had recourse to, and in the course of years find in our public hospitals cases of carbonaceous lung arising from this cause.[19]

It is no uncommon occurrence, in examining the pulmonary structure of those who have resided in large and smoky towns, to find both the substance of the lungs and bronchial glands containing black matter; and this is the case especially with persons who, in such situations, have passed the prime of life. But few, though not living in crowded towns, have not, at some period of their life, come in contact with smoke, and been obliged to breathe it, minutely combined with the air. It is not, therefore, to be supposed improbable, that a portion of the infinitely small particles, thus suspended in the atmosphere, should effect a settlement in the more minute air-cells, and in course of time, be conveyed to the interlobular cellular tissue by the process of absorption, and thence to the bronchial glands. There are several cases on record, from amongst iron-moulders,[20] where the pulmonary structure has been found heavily charged with carbonaceous matter, from the inhalation of the charcoal used in their processes, and where, during life, there was a free black expectoration.[21]

There is, then, little doubt that the bronchial glands, from their appearance in miners, moulders, and others, are the recipients of a portion of impurities which have been carried into the pulmonary structure by inhalation, and also those left after the process of oxygenation of the blood; and when it is fully ascertained, from the character of the atmosphere in the coal mine, that deleterious matter in this form must be conveyed to the air-cells during respiration, there is little difficulty in coming to the conclusion, that the black fluid found to such an extent in these glands in the collier and moulder, is similar to, and a part of, that discovered infiltrated into the substance of the lungs. If we trace the black matter in the lymphatic vessels, (which has been done), from the pulmonary organs to the bronchial, mediastinal, and thoracic glands, and from thence to the thoracic duct, we cannot but admit, that it does find its way into the venous system, and thereby contaminates the vital current.[22]

Dr Pearson of London, in his very valuable paper, published in the Philosophical Transactions of 1813, on the coaly matter in the bronchial glands, was convinced beyond a doubt, that it was of foreign origin, and possessed the properties of carbon conveyed into the lungs from without. He, at that period, was not in possession of such facts as have been recently elicited on the subject of deleterious inhalation; but the very interesting materials which he brought to bear on his argument, have, I think, most satisfactorily proved the assertion which he makes, that "the lymphatics of the lungs absorb a variety of substances, especially this coaly matter, which they convey to the bronchial glands, and thus render them of a black or dark-blue colour." "The texture and proportion of the tinging matter of the glands was," he says, "different in different subjects, whether the lungs to which they belonged were in a healthy or diseased condition. In persons, from about 18 to 20 years of age, some of the bronchial glands contained no tinging black matter at all, but were of a reddish colour; others were streaked or partially black." Again, he says, "I think the charcoal in the pulmonary organs is introduced with the air in breathing. In the air it is suspended in invisible small particles, derived from the burning of coal, wood, and other inflammable materials in common life. It is admitted that the oxygen of atmospherical air passes through the pulmonary air-vesicles or cells into the system of blood-vessels, and it is not improbable, that through the same channel various matters contained in the air may be introduced. But it is highly reasonable to suppose, that the particles of charcoal should be retained in the minutest ramifications of the air-tubes, or even in the air-vesicles under various circumstances, to produce the coloured appearances on the surface, and in the substance of the lungs, as above described."

"When I compare the black lines and black net-like figures, many of them pentagonal, on the surface of the lungs, with the plates of the lymphatic vessels by Cruikshank, Mascagni, and Fyffe, I found an exact resemblance."

Dr Pearson, after various chemical experiments upon the bronchial glands with caustic potash, muriatic and nitric acid, says, "I conceive I am entitled to declare the black matter obtained from the bronchial glands, and from the lungs, to be animal-charcoal in the uncombined state, i.e. not existing as a constituent ingredient of organized animal solids or fluids." Dr Graham of London, in his paper on this subject, recorded in the 42d vol. of the Edinburgh Medical and Surgical Journal, gives the following opinion, as the result of a series of investigations, with the view of determining the nature of the disease in question. He says, I have had several opportunities of substantiating the carbonaceous matter in a state of extraordinary accumulation in black lungs supplied by my medical friends. The black powder, as derived from the lungs, (after an analysis,) is unquestionably charcoal, and the gaseous products from heated air, result from a little water and nitric acid being retained persistently by the charcoal, notwithstanding the repeated washing, but which re-acting on the charcoal at a high temperature, coming off in a state of decomposition. In regard to another analysis of a lung, he says, "The carbonaceous matter of the lung cannot therefore be supposed to be coal, altered by the different chemical processes to which it has been submitted in separating it from the animal matter. The carbonaceous matter of this lung, appears rather to be lamp black."

From the whole results, I am disposed to draw the following conclusions:—

1st, The black matter found in the lungs is not a secretion, but comes from without. The pigmentum nigrum of the ox I find to lose its colour entirely, and to leave only a quantity of white flocks, when rubbed in a mortar with chlorine water. Sepia, which is a preparation of the dark-coloured liquor of the cuttle fish, was also bleached by chlorine, but the black matter of the lungs was not destroyed or bleached in the slightest degree by chlorine, it even survived unimpaired the destruction of the lungs by putrefaction in air.

2d, This foreign matter probably varies in composition in different lungs, but in the cases actually examined, it seems to be little else than lamp black or soot.

It does not appear, as far as I can ascertain, that any of the Continental physiologists are familiar with the disease now under our consideration. Several of them, both ancient and modern, discovered black matter in the pulmonary tissues, but not connected with nor exhibiting the black phthisis. It is therefore unnecessary to refer to them in general.

The following foreign authors entertain various opinions in regard to the dark appearances in the pulmonary tissue:—

Bichat supposes the black matter in the lungs "to be owing to small bronchial glands extending along the surface of the pleura." Breschet believes that it is formed by the blood exhaled into the cellular tissue, stating that its chemical composition leads him to that conclusion. Trousseau says that it is produced by a misdirection of the natural pigments of the body, resulting from age, climate, or disease. Andral says, that the black appearances are the result of secretion, and that it is more manifest as the individual advances in life. Heasinger's opinion is, that it is analogous to pigment, and therefore he agrees with Trousseau. Laennec was doubtful as to the real origin of black pulmonary matter. He makes a distinction between melanotic and pulmonary matter. He found that the melanotic matter was composed almost entirely of albumen, while the black pulmonary matter found in the bronchial glands contains a great quantity of carbon and hydrogen, and also that these colouring matters have other distinguishing characters. The melanotic matter is easily effaced by washing, while the other is removed with difficulty. Laennec further says, that he suspected that this pulmonary matter might arise, at least in part, from the smoke of lamps, and other combustible bodies which are used for heat and light; for some old men are to be met with whose lungs contain very little black matter, and whose bronchial glands are but partially tinged with this colour; and it has struck him that he observed this amongst villagers who had never been accustomed to watch.[23]

Mons. Guillot, physician to the hospital for the aged at Paris, has undertaken a series of researches in regard to the black matter found in the lungs of old men of very considerable age. These investigations are published in the January, February, and March numbers of the Archives Generales de Medecine.[24] It is his belief that death in such cases is owing, in all appearance, more or less to a suppression of the circulation of air and blood by the black substance. His impression is, "that the carbon is not procured from without, but naturally deposited, as life advances, in the substance of the respiratory organs; and that this deposit of carbon causes death, by rendering the lungs irrespirable, while, at the same time, it has much influence in modifying the progress of tubercular disease; so that, if the tubercular affection was not cured, its progress was so far checked, that life has been very long preserved." The black matter envelopes completely both the pulmonary tubercles which have undergone a transformation, and the caverns which no longer contain tuberculous matter. He, while regarding these as the results of black matter in the lungs, throws no light on the cause of the deposit of the particles of carbon within the lungs.

Dr William Craig of Glasgow, in a letter to Mr Graham of London, published in the 42d vol. of the Medical and Surgical Journal of Edinburgh, states most interesting facts connected with this subject, particularly in regard to black matter found in the pulmonary structure of old people, which deserve considerable attention. He says—"I found that a black discoloration of the lungs was by no means a rare occurrence amongst those old people; and that it was impossible in many instances to decide, whether the black colour was owing to an increase of what is called the healthy black matter,—to a morbid secretion, or to a foreign substance being imbedded with the atmospheric air. After examining a considerable number of lungs, and finding that the division of the black matter into three kinds was not founded upon observation, and that the descriptions of them given by the best authorities were insufficient to enable us to distinguish them from one another, I begin to think, that in every instance in which black matter is found in the lungs, it ought to be considered morbid. If we examine the lungs at different stages of life, we find as a general rule that the quantity of black matter increases with age. In young children we find no traces of it, the lungs being of a reddish colour. At the age of ten years the black matter makes its appearance in the outer surface of the lungs, and in the interlobular spaces. At the age of thirty or forty, the lung presents a greyish or mottled appearance, and the bronchial glands contain more or less black matter. Between the age of seventy and a hundred, the lungs are generally infiltrated with fluid black matter, which can be expressed from the cut surfaces, and stain the hands black."

"There are many circumstances which favour the accumulation of this black matter in the lungs; for instance, long-continued living in a smoky atmosphere, like that of this city, the inhalation of coal-dust, as in the case of colliers, or of charcoal-powder, as in the case of iron-founders. There can be no doubt that we inhale foreign substances along with the atmospheric air.

"We find the mucus which has remained in the nostrils for some time to be of a dark colour, and if we examine it with a microscope, we find, that this is owing to the presence of small particles of dust or other foreign substances, which the air may have accidentally contained. The mucus first coughed up from the lungs in the morning, is of a dark colour from the same cause, and the facts now maintained prove, that foreign substances suspended in minute particles in the atmosphere, may be inhaled into the lungs. I believe in all the extreme cases which have occurred in colliers and moulders, that there must have existed some previous disease of the lungs which prevented the foreign matter from being thrown off." "According to the views which we have taken of the subject, there are only two ways by which black matters may be deposited in the lungs; first, by a morbid secretion; second, by a foreign substance inhaled with the atmosphere. The former is a rare disease, while the latter is very common. I am inclined to think that the true melanosis generally occurs in the form of rounded tumours, which, when cut in two, present a uniform black colour without any trace of air-cells, while in the spurious melanosis the deposition is general, and black matter flows freely out when the cut surfaces are pressed. At first the lung is crepitous, and swims in water; but as the black matter increases, it becomes solid, and, as in the case of colliers who die of this disease, resembles a piece of wet peat in point of consistence. It is only in the cases of colliers, moulders, or others who inhale great quantities of black matter, that the lungs are rendered perfectly solid."

There is an exceedingly interesting and valuable paper, written by Dr Brockmann of Clausthal, upon the pulmonary diseases of a certain class of German miners,—supposed to be in the Hartz mountains,—in Neumeister's Repertorium for December 1844, an abridged translation of which is to be found in the September number of the Monthly Journal of Medical Science.

It is very evident that the disease there considered is produced by carbonaceous inhalation, and resembles in all its features the black phthisis so general amongst the colliers in Haddingtonshire. The morbid appearances described by Dr Brockmann are very similar to the first and second division of that disease, presenting a very general carbonaceous infiltration of the pulmonary tissues; but in none of the stages are there to be found the extensive excavations discovered in the lungs of the coal-miner. Dr Brockmann makes three divisions of the morbid appearances, "The essential (wesentliche), accidental (zufaellige), and secondary. The first shows an entirely black (pechschwaerze) colour of the lungs through its whole substance, enclosing not only the air, blood, and lymph vessels, but also the connecting cellular tissue, the nervous substance, pleurae pulmonalis, and bronchial glands." In such a state, it is usual for the lung to remain perfectly normal, and to exhibit the greatest varieties.

The accidental (zufaellige) is evidently the disease in a more advanced form, corresponding in a great measure with the second stage of the morbid action, found in the pulmonary organ of the collier. It is to be regretted that no accurate description is given either of the character of the mine, or the nature of the employment in which the miners are engaged, whether they be coal, silver, or lead mines, and if they are in the habit of burning coarse lint-seed oil.

There is a very striking similarity between what Dr Brockmann calls the secondary anatomical changes, and many of those exhibited in the collier; first, membranes; second, collections of fluid into the pleurae and pericardium; third, the softened heart, and very general emaciation; fourth, the extensive venous congestion, with thick black blood.

The liver is described by Dr Brockmann as being small:—in the collier it is usually puffy, and much congested.

The symptoms do almost in all points accord with those presented in the collier, as will appear from the following quotation, from the paper. "In the first stage, there is no local, functional, or general feature by which we can ascertain that the disease has commenced; probability is all we can reach. In the second stage, the disease is more obvious. And, first, there is a change in the expression of countenance; to a fine blooming appearance, which perhaps the patient previously had, there has succeeded a dark yellowish cast,—a change which gradually spreads over the whole body. For some time the patient may have remarked a gradual loss of strength, and now he complains of want of appetite and disordered digestion, and more particularly of shooting pains in the back and muscles of the chest. Cough likewise supervenes, which may either be quite dry, or at most accompanied with a little pure mucus. There is also a greater or less degree of oppression, accompanied with palpitation of heart, not only after a severe fit of coughing, but after every exertion of the lungs. As yet no local deviation from the normal condition is seen on examination of the chest by percussion or auscultation." "The disease meanwhile passes into the third stage. The features of the patient now become more and more changed and deteriorated, and betray a deep melancholy. The colour of the face, which had been hitherto of an earthly hue, becomes blackish, as also the cornea, whereby the eye loses its lustre. The appearance of the patient becomes still more frightful from the great loss of flesh, and the dark skin hanging loose on his bones. The fat not only seems to have disappeared, but the muscular substance also—the whole frame being shrivelled. The patient complains of increasing weakness, diminished appetite, flying pains often concentrated at the pit of the stomach; and coughs much. The expectoration is for the most part difficult, and consists of masses of mucus, either greyish, or tending to a black colour. A black streak is frequently observed running through the whitish mucus; one half of it may be white, the other black, or occasional black points may be observed throughout the mass, and sometimes, though rarely, blood. Dyspnoea is usually connected with the cough. It now begins to tell upon the patient, and is so characteristic, that the disease has been named asthma metallicum. The disturbance of the digestive organs increases the disease,—the appetite is entirely lost,—the tongue is covered with a white fur—there is an oppression at the stomach after a full meal—frequent eructations, and a tendency to constipation. The distress of the patient becomes increased in consequence of the shooting pains in the muscular system." "In the fourth and last stage, all the external appearances indicate the near approach of dissolution,—the face and members become bloated, and the feet greatly swollen." "The dyspnoea meanwhile, from effusion into the chest and pericardium, becomes so severe, that the patient cannot maintain the horizontal position, the expectoration becomes copious, consisting of a black inky (dintenschwarze), or ash-coloured fluid, sometimes of mere masses of mucus streaked with black." "The disease is never accompanied with colliquative sweats or diarrhoea."

I am sorry to find that there is no allusion whatever to the state of the pulse. Dr Brockmann, in his remarks on the essential nature of this pulmonary disease of miners, brought under his notice, seems to entertain the impression that along with the inhaled carbon, resulting from the combustion of gunpowder, there is also an organic pigment-deposit present in the pulmonary tissue, which he supposes must have been formed in the lungs.

I have long entertained the belief, which I have stated in another part of this essay, that if the carbon is once conveyed into, and established in the parenchyma of the lungs, that organ commences the formation of carbon; thus increasing the amount originally deposited. Dr Brockmann sets forth, as grounds for this view, that "if the parenchyma of the lungs were filled with carbonaceous dust, their specific gravity ought to be increased; but this is not the case. A completely melanosed lung swims in water, both as a whole and when cut into parts." It is very evident from these remarks, that the author has not seen the disease as it is exhibited in the third division of morbid action in the collier, otherwise he would have both observed the lungs considerably augmented in weight, and also so densely impacted from the accumulation of carbon, as wholly to sink in water. See for instance case No. 2, where the lungs weighed about six pounds, and parts of the cellular tissue were so indurated, as to be cut with difficulty. In this case, the patient did not expectorate.

Dr Brockmann, as he advances, puts a question here, which more fully shows that the disease under his consideration was of a mild character compared with that under our notice. "If," says he, "pulmonary melanosis arise entirely from inhalation of carbonaceous dust, why is it not observed in other workmen, who are as much, and even more, exposed to its influence, as for instance, smelters, or moulders, and colliers?" He says, further, "were the carbon inhaled in quantity sufficient to explain the black colour of the lungs, it ought also, from its mechanical irritation, to produce inflammation in the delicate mucous membrane of the organ, but there are no symptoms of this during life, nor any traces of it after death." An answer to these remarks will be most satisfactorily given by a reference to the published cases, where the disease is principally found amongst colliers and moulders, and where the pulmonary organs, particularly in the former, are found to undergo most fearful disorganization from the presence of carbon. It is very remarkable, that the author of these exceedingly interesting observations should never have found excavations of the parenchyma, when it is so general as the result of the same disease in this country, particularly in the locality to which I refer. Not knowing the character of the mine, it is impossible to judge; but I am disposed to conclude that there cannot be the same quantity of carbon floating in the atmosphere breathed by the German miner,—the disease resembles very much that milder form found in the iron moulder.

With regard to the carbonaceous state of the blood, I am sorry that I have not yet completed my investigations on that subject. It is still my belief that the carbon being once inhaled, there is an affinity found for that in the circulating fluid, and from its not being consumed, owing to a deficiency of oxygen, there is a progressive increase going on. I am very much gratified to find that Dr Brockmann entertains a somewhat similar opinion in respect to the state of the blood.

The effects of such a morbid structure upon the collier population in general is very marked. Previous to the late legislative act, the tender youth of both sexes were at an early age consigned to the coal pit, and obliged to labour beyond their feeble strength, in circumstances ill adapted to their years. Such early bodily exhaustion soon produced in them a pallid countenance, soft and relaxed muscular fibre, and predisposed much to disease as they advanced in life. The miner on this account was generally from his youth, thin; in fact, you never see a fat and healthy-looking collier, and, according to the advance of pulmonary disease, with them, so is the progress of emaciation. Such a state of body may well be looked for in miners, labouring as they do, from ten to twelve hours in the twenty-four under ground, breathing a heated and impure atmosphere, which with difficulty sustains life, and which is demonstrably calculated, from its deleterious qualities, to induce serious disease. The effects manifest in the parent descend, and visible in the youngest children; they are squalid and wretched-looking,—and how can such offspring be otherwise? They are exceedingly subject to all children's diseases, and peculiarly predisposed to pulmonary irritation of one kind or other.

With regard to medical treatment, little can be done after the disease has passed its first stage. Early removal from the occupation, and proper attention to nutrition, alone seem to hold out the hope of prolonging the life of the patient; but if there be carbon lodged in the pulmonary tissues, there is a certainty of its sooner or later proving fatal. Attention to the state of the digestive organs, and using every means to remove the dyspeptic symptoms, which are prominently present throughout the various stages of this disease, are indispensably requisite; and, as to nutrition, the nature of the diet should be as generous as possible. Anodynes and expectorants are the only remedies which seem at all efficacious in allaying irritation.

With a view to remove urgent symptoms, venesection has repeatedly been had recourse to, but in almost all instances I would say, with decidedly bad effects. Blood-letting does harm, producing general debility and rapid sinking.[25]

With regard to the prevention of this disease, ventilation, as has been stated, is very much neglected in the pits now under consideration, where the various cases have occurred; and to that neglect I ascribe the prevalence of the malady. In those pits referred to, the workable apartments are so confined, and become after a time so destitute of oxygen, as, along with the smoke from lamps and gunpowder, to render the air unfit for healthy respiration. The only effectual remedy is a free admission of pure air, so applied as to remove the confined smoke. This remark both applies to coal and stone-mining. The introduction of some other mode of lighting such pits than by oil is required. I know several coal-pits where there is no carbonaceous disease, nor was it ever known; and on examination I find that there is and ever has been in them a free circulation of air. For example, the Penston coal-work, which joins Pencaitland, has ever been free from this disease; but many of the Penston colliers, on coming to work at Pencaitland, have been seized with, and died shortly after, of the black spit: for instance, G. case No. 5, and D. case No. 8, are such.

How this is to be accomplished, is for the scientific man to say. With all due deference, I may be allowed to suggest various modes which might be adopted to free the underground atmosphere of the noxious ingredients. Could fresh air not be forced down by the power of the steam-engine, which is at every coal-pit? Could extensive fanners not be erected and propelled by the same machinery?[26] I am much surprised that no attempt has been made to light these pits with portable gas in some way or other. As far as I can understand, such an application of it would not be difficult. A small gasometer could be erected, and the necessary apparatus procured at little expense, and by such means, I would suppose, it could be carried to any part of the mines, which are not extensive.

Many proprietors may grudge the expense involved in such improvements, and thus prove a barrier to these necessary alterations; but I would ask any candid and generous mind, what is expense when the object in view is the removal of a disease to which many human beings fall a sacrifice?[27]

It must appear to every one that these collier diseases are crying evils, the preventive of which is based, as will be seen, on thorough ventilation; and in order to protect the miner, there should be a vigilant attention paid to the economy of underground works. No one need be surprised at the result of such a noxious atmosphere; and it becomes a duty with the government to protect these poor people by laws, and to adopt those measures which are best calculated to preserve their health; and should there arise difficulties of an insurmountable character in the ventilation of these pits, why continue the mining operation in such situations at such a sacrifice of human life?[28]

* * * * *

In the course of my investigations in regard to pulmonary carbonaceous infiltration, I was led to consider the circumstances of those engaged in other occupations than coal-mining. Any one who has carefully examined the structure of the human bronchial glands, at different epochs of life, must have been struck with their appearance in those who, from their vocation, are compelled to breathe a sooty atmosphere, or who have lived in ill ventilated dwellings.

I am further convinced, from the results of my recent investigations, that the bronchial glands in such persons invariably contain carbonaceous matter which has been inhaled at some period of life. Having long entertained the belief that the lungs of chimney sweeps, for example, would, in all probability, be found to contain carbon, within the last few months two cases, of an exceedingly interesting character, connected with the present inquiry, have presented themselves,—the one of pulmonary disease, evidently resulting from the bronchial and lymphatic glands being impacted with inhaled carbon derived from soot,—the other a case of melanosis occurring in a young person. Though the two diseases differ materially, they have often been confounded with each other and assigned to the same cause. My object in here reporting a case of stratiform melanosis, in connection with a disease having an external origin, is to afford an illustration of the fact, that all black deposits found in the system are not carbon. There exists a marked chemical distinction between the melanotic and the carbonaceous matter; and the anatomical situation of the two is also different.

CASE.—A chimney sweep, aged 50, of the name of Campbell, residing at Stockbridge. The short history of his case I procured from his friends, as I did not see him during his illness. He had been a soldier in early life, and had seen much foreign service. After he relinquished the army, he became a chimney sweep, in which capacity he was constantly engaged for nearly twenty years. He had had, for a considerable time, a troublesome cough with tough expectoration. He experienced a difficulty of breathing in making any exertion, and he had considerable oedema of the limbs. From these symptoms he believed that he was subject to asthma. He had only been confined to bed for two days previous to his death.

Post-mortem Appearances.—The body exhibited extensive anasarca; the thorax was well arched; the cartilages of the ribs were ossified. On removing the anterior part of the chest, the pleurae were found to adhere strongly, and appeared rough and puckered from extensive exudation of a brown colour, which extended very generally over the serous membranes. Both cavities contained nearly three gallons of light brown fluid. The pericardium was considerably distended with a straw-coloured fluid, and several flakes of lymph floated throughout the effusion. Both auricles of the heart were enlarged, and distended with exceedingly dark blood. The walls of both ventricles were much thickened. The valvular structure of the auricles was congested and granular. The lungs were removed from the chest with difficulty, owing to the very general pleuritic adhesions. Both exhibited extensive emphysema. In dividing the lungs, and tracing the bronchial ramifications, each lobe was found to contain clusters of enlarged and indurated bronchial glands, impacted with thick black matter; and prosecuting the investigations, the minute lymphatic glands were observed clustered in a similar manner, and containing black fluid. In the substance of the upper lobe of both lungs, the bronchial glands were of a bright black colour; they were particularly large, and so numerous as to press considerably upon and obstruct several of the bronchial tubes. In fact the upper lobe of both lungs exhibited the plum-pudding structure. At the bifurcation and back part of the trachea, the bronchial glands were numerous, and of a deep black colour. A considerable mass of the glandular structure was removed for chemical and microscopic examination.

The second case was that of a boy aged six years, who was under treatment for an affection of the heart and kidneys, and who died apparently from disease of these organs. He was, during his whole life, of a relaxed and weakly constitution, exceedingly sallow in the complexion, with a very deep blue tint of the sclerotic coat of the eye. In the course of the post-mortem examination, there was discovered, in the lower and lateral part of the right pleura, a cyst containing about an ounce of semi-fluid melanotic matter; and also the morbid secretion presented the stratified appearance described by Dr Carswell in his article upon Melanosis, extending over the inferior half of the costal pleura and the corresponding part of the diaphragm. It formed a distinct layer on the surface of the serous membrane, resembling ink or blacking, and could with difficulty be removed. The black deposit resembled much in appearance the foreign matter found in the pulmonary organs of the coal-miner, and therefore was submitted, as well as the bronchial glands in the other case, to chemical analysis, with the view of ascertaining if there existed any analogy in the component parts of each.

Dr Douglas Maclagan submitted both these substances to the action of concentrated nitric acid, and the results were, that the glandular structure of the chimney sweep contained a very large proportion of carbon, while of the contents of the melanotic cyst, the same process did not leave a vestige of colouring matter,—evidently proving the distinction which exists between those two dark deposits, and making it sufficiently obvious, that melanotic matter is composed of the constituent elements of the blood, and has its origin within the body. There cannot remain a doubt as to the nature of the chimney sweeper's case; for, from the knowledge which we have of his occupation, and from the chemical properties manifest after investigation, I think I am entitled to declare the black matter obtained from the bronchial glands to be carbon inhaled with the air during his labour, and not existing as a constituent ingredient of organized solids or fluids.

The microscopic examination showed the carbon most distinctly in a molecular form.

It is my intention to return to this subject at a future time.

NORTHUMBERLAND STREET, EDINBURGH, January 1846.

* * * * *

FOOTNOTES:

[1] Vide an admirable series of papers on this subject in the volume of this Journal for 1843, by Dr Calvert Holland.

[2] About ten miles east from Edinburgh.

[3] Generated from the decay of vegetable and other substances in the formerly wrought pits, which communicate with those at present in use.

[4] It is proved, from the difference in the chemical character possessed by the melanotic matter, as compared with the matter found in the lungs of miners.

[5] It will be observed, that, though the small blood vessels are destroyed, no hemorrhage takes place, owing to the formation of a carbonaceous plug.

[6] The air of the coal-pit is so charged with carbon as to prevent the collier from distinguishing his neighbour when at work.

[7] Note from the evidence of a collier examined before the Government Commissioners in 1842, No. 147 of Report. "Colliers in this part of the country are subject to many oppressions; first, Black spit, which attacks the men as soon as they get the length of 30 years of age;" second, Note 150, "The want of proper ventilation in the pit is the chief cause, and no part requires more looking after than East Lothian," the men die off like rotten sheep. Note, 153, the witness, 32 years old, says, "I am unable to labour much now, as I am fashed with bad breathing—the air below is very bad, and till lately no ventilation existed."

[8] The black sputum retains its colour after being submitted for some days to the action of nitric acid.

[9] This is the only case in which I at any time observed colliquative sweats as a symptom of this disease.

[10] To convey an impression of the nature of the labour in which the man was engaged I shall simply extract a few remarks from the evidence of the miners at this coal-work, taken by Mr Franks for the Government's Commissioners, Note 105. "At all times the air is foul, and the lamps never burn bright. The seam of coal is 24 inches, and the road only three feet high." Note 108—"Experienced colliers do not like the work, and many are touched in the breath." And in such a situation man is doomed to labour! Note 114—"Most of the men here are fashed with that trouble; Foster, Miller, Blyth, and Aitken are all clean gone in the breath together. Colliers here drop down very soon."

[11] It is evident in this disease that the bronchial ramifications are destroyed, while the arteries, with the exception of the minute twigs, are preserved.

[12] One of the lungs (the left one) now described, I sent to Dr John Thomson, late Professor of Pathology, and will probably be found in his collection, which I understand is in the College of Surgeons.

[13] After a free expectoration of black matter, there was an evident mitigation of all the pectoral symptoms, and as the carbon again accumulated in the lungs, the sufferings of the patient were very considerably increased.

[14] This sputum was subjected to the action of nitric acid, which produced no effect upon its colour.

[15] When pulmonary disorganization has proceeded far, from the presence of carbon, there is a languor in the vital action from defective oxygenation of the blood, which produces a gradual reduction in the temperature of the body, requiring double clothing, and even that addition is, with the aid of stimulants, not sufficient to keep the patient warm.

[16] This lung is in the possession of Sir James Clark, of London.

[17] The above substances were submitted separately to the action of nitric acid and caustic potash, and the result was that a large proportion of carbon was precipitated.

[18] Since writing the above the patient has died; and I regret that, owing to neglect in communicating with me, I have been prevented examining the morbid appearances.

[19] Several of the Pencaitland colliers are at present engaged in the tunnelling operations near to Edinburgh, connected with the North British Railway.

[20] Dr Hamilton's of Falkirk paper in the Edin. Med. and Surgical Journal, Vol. xlii.

[21] I have very lately, through the kindness of Mr Girdwood, surgeon at Falkirk, had an opportunity of examining two or three iron-moulders in that district. Both from the nature of the employment in those iron works, and the character which the pulmonary affection exhibits, the fact of inhalation is fully established. The moulder is at a certain stage of his labour enveloped in a cloud of finely-ground charcoal, a portion of which cannot fail to find its way to the lungs in breathing. He is subject to tickling cough, and as the disease advances, the respiratory sounds, which indicate considerable bronchial irritation, present themselves, and ultimately become dull, and in some parts obscure.

Of the several cases which I saw with Mr Girdwood, one, who has not been labouring for some years as a moulder, occasionally expectorated black matter, and in the other two, there was general dullness of both lungs; and, I doubt not, impaction.

[22] It has not been in my power hitherto to procure so satisfactory a chemical analysis of the blood as I would wish, but through the kind assistance of Dr Douglas Maclagan, who has undertaken to conduct the process, I expect very soon to be able to lay it before the profession.

[23] I found little or no black matter in the lungs of farm servants, who are much in the open air.

[24] Vide MONTHLY JOURNAL for 1845, p. 702.

[25] At any time when these colliers required venesection, particularly towards the last stage of the disease, the blood appeared peculiarly dark and treacle-like.

[26] Could oxygen not be prepared and forced down?

[27] I am happy to find that the attention of the noble proprietor of the Newbattle coal works is now directed to this subject.

[28] I cannot pass from this subject without an observation on the beneficial results which have been the consequence of Lord Ashley's valuable colliery Act. The female Labourers, and particularly the unmarried, have improved not only in their appearance, but also in general physical development, since they have abandoned the unhealthy labour of the coal-mine. They are no longer the squalid, filthy, and ill-favoured race they formerly were. There is now exhibited on the face of the collier girl the bloom of health and cheerfulness; and when we descend to their domestic economy, there is observed a comfort in the management of their households, which formerly did not exist. Their children are now particularly cared for, both in health and when suffering from disease; and we must regard this early watching as an important step to the removal of that predisposition to pulmonary irritation, so general in the collier community.

THE END