3 h THE POPULAR SCIENCE MONTHLY. 



Now, I think no one would care to attempt fine spinning 

 nnder a hot sun where the humidity of the outer atmosphere 

 changed between seven o'clock in the morning and three o'clock in 

 the afternoon from 84 per cent of moisture to 38, or from 93 to 50. 

 Bear in mind that the variation charted, as I have presented it, is 

 the mean variation of each and every day, averaged by months. 

 It will be observed that this change in the humidity of the air 

 makes the heat more comfortable and more easy to bear ; that is 

 the reason why our Southern friends complain of the heat of the 

 summer as compared with their own when they come North ; 

 but, whether these conditions and variations are conducive to 

 spinning and weaving cotton, my hearers are better judges than 

 I am. 



It may be remembered that we took this subject up some years 

 ago, but I do not think it was then ripe. It might be judicious 

 for the association to make some arrangement for a very thor- 

 ough and complete study of this matter, in connection with a very 

 visionary proposition which I am about to submit, for making 

 use of freezing apparatus in tempering and controlling the air of 

 factories. I was unable to take this subject into consideration 

 until very lately, and I need to apologize for the superficial treat- 

 ment which I have given it. I introduce it because I think it 

 may be a most important and perhaps the paramount factor in de- 

 termining 



1. Where the coarse work, 13 to 20, may be done. 



2. Where the medium, 20 to 40, may be carried on without dis- 

 advantage. 



enabled to furnish the figures by means of which the mean temperature and the mean 

 relative humidity at New Bedford have been compiled for the year 1881. The results are 

 as follow : 



Mean temperature, dry bulb 48'9 F. 



Wet bulb 46 -4 F. 



Mean relative humidity, 7 a. m 90 per cent. 



Mean relative humidity, 2 p. m *74 " 



Mean relative humidity, 9 p. m 90 " 



Mean of the year 84 " 



Maximum during the year 100 " 



Minimum during the year 60 " 



I have also received readings for the mean relative humidity of Prestwich, a suburb of 

 Manchester, in Lancashire, but not situated high above the sea on the crest, like the Old- 

 ham district, Prestwich being only 294 feet above the sea-level. The readings for 9 a. m. 

 show a mean relative humidity of 84 per cent ; for 9 p. m., 87 - 6 per cent. There is no mid- 

 day observation. The variations morning and night correspond very closely with those of 

 New Bedford, the relative humidity being a little lower. 



I am led to believe, from all that I can learn, that so far as atmospheric conditions 

 constitute a factor in cotton-spinning, the conditions of the southern coast of New England, 

 where the climate is affected by the moisture from the Gulf Stream, are as favorable as 

 those of Lancashire to any kind of work. 



