Proceedings. 55 



Ordinary Meeting, October 29, 1889. 



Professor Osborne Reynolds, M.A., LL.D., F.R.S., 

 President, in the Chair. 



It was announced that the Council had formally decided 

 to initiate a movement for the erection in Manchester of a 

 memorial of the late Dr. J. P. Joule, and had appointed a 

 sub-committee to prepare a memorial to the Mayor of 

 Manchester — requesting him to summon a public meeting 

 to that end — and to obtain signatures to such memorial. 



Mr. H. H. HOWORTH, M.P., read a portion of a paper 

 " On Dr. Croll's Theory of Alternate Glacial and Warm 

 Periods in each Hemisphere and of Inter-Glacial Climates," 

 contending especially that the equatorial calms are not 

 caused by the conflict between the north-east and south- 

 east trade winds, "which never come into conflict," but 

 mark the region where the air, being hottest and most 

 charged with moisture, takes an upward motion. Secondly, 

 he argued that the trade winds do not blow towards the 

 earth's equator, but to the latitude of greatest mean heat, 

 which does not coincide with the earth's equator and is 

 never south of the equator, its mean being always 10 

 degrees north. This position is caused by the great pre- 

 ponderance of land over water in the northern hemisphere, 

 as is shown by the isothermals. For these reasons, Mr. 

 Howorth submitted that Dr. Croll's notion, that the position 

 of the equatorial calms is due to the southern trade winds 

 being stronger than the northern, is inadmissible. Inasmuch 

 as the distribution of land and water was very much the 

 same in the glacial age as now, it follows that the position 

 of the heat equator must have been the same, and there is, 

 therefore, no room for Dr. Croll's conclusion that the 



