1. =Dead Substances= inhaled for a prolonged period in various occupations are a common cause of premature death. The _potter_ draws into his lungs a fine silicious dust, which irritates his lungs, and finally produces a fatal disease, known as =potter’s asthma=. =Mill-stone Cutters= and =Stone Masons= inhale the fine particles of stone given off from the material which is being chiselled. These produce serious disease of the lungs. =Pearl Cutters= inhale fine particles of pearl-dust, and as they generally work in close rooms, and the dust is light and tasteless, serious disease of the lungs results. =Sand-paper Makers= inhale minute portions of glass and sand; and =needle and knife grinders= are exposed to similar dangers, and at one time the mortality among them was frightful. It has greatly diminished since the introduction of wet grinding, the use of steam fans, and wearing of respirators. =Hemp and Flax Dressers= inhale a dust which is peculiarly irritating. =Workers in rags and in wool= suffer in like manner from dust. The dust from fleeces of wool, and especially from the alpaca fleece, has produced in many cases (in the neighbourhood of Bradford and elsewhere) an acute disease (anthrax) proving fatal in a few days. The spores of this disease are very persistent of life (page 274), and remain active for mischief for months after the death of the animal which had suffered from it. The fleece can be disinfected by steam; and the use of fans for diverting the dust created during “sorting” minimises the danger from it. The =miller= commonly suffers from a form of asthma, not so severe as potter’s asthma, as the particles in this case are not equally irritating. The =hairdresser= is liable to inhale the short fragments of hair cut by the scissors, and the mortality of this class of workers is high. =Miners= in coal have a surprisingly low mortality, when accidents are excluded from the calculation; except in South Wales, where it is slightly higher than for all males in the same district. Coal dust is relatively free from sharp angles, and is therefore not so irritating to the lungs as metallic dust. Consumption is relatively rare among miners. =The Fur-dyer= is very prone to suffer from the dust of the dyed furs, great irritation and disease resulting in many cases. =Artificial Flower-makers=, and those engaged in colouring arsenical wall-papers, suffer from the inhalation of arsenical vapours, as well as from the irritating effects of its absorption by the skin. These are now seldom seen, owing to the almost complete abandonment of the use of arsenic for wall-pigments. =Cigar-makers= are liable to have their lungs irritated by inhalation of the dust of the tobacco-leaf; and may suffer from tobacco-poisoning.