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 œdema 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 pleuræ 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.