This section is from the book "Materia Medica And Therapeutics Inorganic Substances", by Charles D. F. Phillips. Also available from Amazon: Materia medica and therapeutics.
In cases with much cough and profuse secretion, sulphur will often relieve, lessening and modifying the expectoration. I have seen this accomplished in many instances. The old physicians described it as "balsamum pectoris," and it still forms part of some quack "nostrums." Dr. Graves records his experience in its favor. Binz suggests that sulphuretted hydrogen, being excreted by the bronchial mucous membrane, may partially narcotize the terminals of irritated bronchial nerves, and advocates for the continued use of small doses of sulphur in asthma are not wanting (Duclos: Bulletin, 18G1). I have seen cases marked by loud wheezing, profuse but difficult expectoration, troublesome palpitation, and nocturnal spasms of severe dyspnoea, improve quickly with 5 to 10 gr. of sulphur taken thrice daily. The sulphur springs of Weilbach are celebrated for relieving cases of chronic bronchitis, especially when complicated with haemorrhoids.