200 SCIENCE IN SHORT CHAPTERS. 



quite satisfies me that I could do a fair day's work of six or 

 eight hours in a temperature of 130 F., provided I were 

 free from the encumbrances of clothing, and had access to 

 abundance of tepid water. This in a still atmosphere: but 

 with a moving current of dry air capable of promoting 

 vigorous evaporation from the skin, I suspect that the 

 temperature might be ten or fifteen degrees higher. I 

 enjoy ordinary walking exercise in a well-ventilated Turkish 

 bath at 150, and can endure it at 180. 



In order to obtain further information on this point, I 

 have written to Mr. Tyndall, the proprietor of the Turkish 

 baths at Newington Butts. He is an architect, who has 

 had considerable experience in the employment of workmen 

 and in the construction of Turkish baths and other hot-air 

 chambers. He says: " Shampooers work in my establish- 

 ment from four to five hours at a time in a moist atmos- 

 phere at a temperature ranging from 105 to 110. I have 

 myself worked twenty hours out of twenty-four in one day 

 in a temperature over 110. Once for one half-hour I 

 shampooed in 185. At the enamel works in Pimlico, 

 belonging to Mr. Mackenzie, men work daily in a heat of 

 over 300. The moment a man working in a 110 heat 

 begins to drink alcohol, his tongue gets parched, and he is 

 obliged to continue drinking while at work, and the brain 

 gets so excited that he cannot do half the amount. I 

 painted my skylights, taking me about four hours, at a 

 temperature of about 145; also tne hottest room skylights, 

 which took me one hour, coming out at intervals for " a 

 cooler," at a temperature of 180. I may add in con- 

 clusion, that a man can work well in a moist temperature of 

 110 if he perspires freely." 



The following, by a writer whose testimony may be 

 safely accepted, is extracted from an account of ordinary 

 passenger ships of the Red Sea, in the "Illustrated News,'" 

 of November 9, 1872: " The temperature in the stoke-hole 

 was 145. The floor of this warm region is close to the 

 ship's keel, so it is very far below. There are twelve 

 boilers, six on each side, each with a blazing furnace, 

 which has to be opened at regular intervals to put in new 

 coals, or to be poked up Avith long iron rods. This is the 



