338 



SCIENCE 



[N. S. Vol. LIII. No. 1371 



bulb is heated in hot water in a thermos flask 

 until the meniscus rises into the small top 

 of the bulb. It is then dried, suspended and 

 the time of cooling- from 100° to 95° F. taken 

 with a stop watch in seconds. The number 

 of seconds, divided into a factor number (ap- 

 proximately 500, and determined for each in- 

 strument) gives the cooling power by con- 

 vection and radiation on the surface of the 

 " kata " at approximately skin temperature 

 in millicalories per square centimeter per 

 second. The operation is repeated with a 

 cotton muslin finger stall on the bulb and 

 the wet " kata " cooling power obtained, a 

 cooling power due to evaporation, radiation 

 and convection. The difference between the 

 two readings gives the cooling power of the 

 evajwration alone. 



It is shown by a table to what low values 

 the cooling jiower can fall in stagnant air at 

 even moderate temperatures — values that are 

 much too low for any except the most seden- 

 iary occupations. And yet it is true that in 

 many factories and mills where great heat 

 is generated by rapidly moving machinery, 

 or where workmen are subjected to high tem- 

 peratures in engine rooms and about furnaces, 

 no provision is made for the introduction of 

 cool air, nor even for keeping the warm air in 

 circulation. The result is that the proper 

 vigorous activity of the respiratory and 

 vascular organs is not maintained and ill- 

 ness, or general depression, with its conse- 

 quent inefficiency results. An excellent ex- 

 am.ple of the effect of providing proper means 

 for cooling is that of a large steel tube fac- 

 tory in England, where air ducts supply air 

 so cool that the men working before the huge 

 furnaces actually feel cool when the furnace 

 doors are shut. The effect is quite like the 

 heating and cooling on a summer's day with 

 passing clouds. It is said that the output of 

 that factory is greater than that of any other 

 of its kind, and there is no industrial unrest. 

 Thus it is, that by reproducing as far as 

 possible within doors the slight variations of 

 temperature and air movement which out- 

 door workers experience, it is possible to make 

 some progress in keeping the sedentary worker 



in the same robust and vigorous physical con- 

 dition in which the outdoor worker finds him- 

 self. The economic importance of giving at- 

 tention to these considerations is obvious. 



A study of the relations between weather 

 conditions and the incidence of certain dis- 

 eases in north Atlantic states has been made 

 by Mr. John E. Weeks, U. S. Weather 

 Bureau meteorologist at Binghamton, N". T.* 

 From his studies he has drawn the following 

 conclusions : 



First, that a moderate degree of humidity, 

 about 70 per cent., and a moderate tempera- 

 ture, about 68° F., should be maintained in 

 dwellings ; 



Second, that crowding and mingling with 

 I)ersons having cough should be avoided; 



Third, that sunshine and plenty of interior 

 light should be sought; and 



Fourth, that schools for janitors should be 

 provided in order that the heating and venti- 

 lation of public places may be properly cared 

 for. 



The objection that a relative humidity as 

 high as 70 per cent, indoors in winter would 

 be difficult to maintain with a temperature 

 as high as 68° F. is, no doubt, a valid one; 

 but such a temperature would probably be 

 too high for comfort with that humidity. 

 Since it would be much easier to maintain a 

 high humidity with a lower temperature it 

 probably would be possible to find a practic- 

 able combination of temx)erature and humid- 

 ity which would be entirely comfortable. In 

 an article by William E. Watt, principal of 

 the Graham Public School, Chicago, on 

 " How I run my school,"' it is found that a 

 temperature of 60° F. is sufficiently high for 

 comfort if sufficient humidity is maintained. 

 By introducing live steam into his warm air 

 ducts he found it possible to maintain such 

 conditions, with beneficial results to teachers 

 and pupils. 



In addition to the necessity for local con- 



6 Abstract and discussion in Bulletin of the 

 American Meteorological Society, February, 1921, 

 pp. 27-28. 



7 The Ladies' Home Journal, September 1, 1910, 

 p. 20. 



