Very frequently, too, these long hours at an intense strain must be spent at work positively dangerous on account of the process, such as matchmaking[72] or painting lamps.[73] Chemical poisoning is frequent in hatters' and furriers' work, and plumbism, which is very similar to phosphorous poisoning, besets any trade in which lead is used. This is the case, in the production of white, red, or yellow lead, industries in which goods dyed with them undergo the process of building, winding, weaving, etc., and such an apparently innocuous occupation as the manufacture of earthenware and pottery. "One of the first symptoms of plumbism is a blue gum, followed by loosening and dropping out of the teeth. Blindness, paralysis, and death in convulsions frequently follow. Besides plumbism there are serious indirect results from lead-poisoning in a number of industries."[74] Readers of George Bernard Shaw will remember that Mrs. Warren adopted her profession through fear of contracting this disease. Her sister had fallen a victim to it and the frightful ravages made among her friends drove her to this course. In other industries such as wool sorting, blanket stoving and tentering, and warp dressing, lock-jaw is an incident. Closely allied to a question already discussed, that of ventilations, is the insidious injury wrought by dust in the air. Some trades in which this condition is pronounced, seem materially to shorten life, as shown by a bulletin of the United States Bureau of Labor for May, 1909, on "Mortality from Consumption in Certain Occupations." The proportion of those reaching the age of 65 and over among tobacco and cigar factory operatives was 1.8%; glove-makers, 2.3%; bakers, 2.4%; leather curriers and tanners, 2.9%; and confectioners, 3.1%: as against 4.7%, the average expected normal on the basis of all occupied males in the United States (l. c., p. 623). Eighty-nine per cent. of the clergymen who died in 1900 were over 44, and 55% over 65 years of age; 76% of the lawyers dying in this year were over 44, and 41% over 65; 73% and 41% of the physicians had passed these respective ages; 80% and 37% of the bankers, officials of companies, etc., were over 44 and 65: yet more than half of the compositors dying in the United States for the year were under 49 years of age. About one-half of these died of pulmonary tuberculosis. Only 18% were over 60.[75] Between 1892 and 1898, 32% of the deaths of glass bottle-blowers were due to tuberculosis, largely induced, probably, by the strain on the lungs, the "blow-over," and conditions of temperature.[76] Industrial mortality insurance statistics show that 23% of the deaths of those employed in trades exposed to organic dust are from consumption and 14% from other respiratory diseases, as against 14.8% and 11.7%, the expected respective averages for the United States.[77] The following table taken from the bulletin just quoted will probably exhibit the results more strikingly (p. 626):