OCTOBEB 26, 1906.] 



SCIENCE. 



581 



sion in New York City,' by Dr. C. E. Caspari, 

 attracted a very full attendance of members 

 and invited guests. Dr. Caspari had attended 

 the sessions of the commission as a representa- 

 tive of. two firms of New York City, hence his 

 communication had all the interest of per- 

 sonal knowledge. A rather lively and pro- 

 longed discussion of the subject from the 

 chemical and pharmaceutical point of view 

 manifested the interest of the members in 

 subject matter of the law and the law itself. 



C. J. BORGMEYER, 



Corresponding Secretary. 



THE ELISHA MITCHELL SCIENTIFIC SOCIETY OF 

 THE UNIVERSITY OF NORTH CAROLINA. 



The 167th meeting of the Elisha Mitchell 

 Scientific Society was held in the main lec- 

 ture hall of the new Chemical Laboratory on 

 Tuesday evening, October 9, at 7:30 o'clock. 

 The following papers were presented: 



Peofessok Colliee Cobb : ' Geology and For- 

 estry in the Ducktown Region.' 



Mr. Hampden Hill : ' Deforesting of the Duck- 

 town Region by Sulphur Fumes.' 



Professor Chas. H. Heety: 'The Electric 

 Smelting of Iron Ores.' 



DISCUSSION AND CORRESPONDENCE. 

 'an IGNORED THEORY OF THE ICE AGE.' 



In Science (October 5, page 439) there is a 

 communication from Dr. J. M. Schaeberle, 

 under the above title, of which the following 

 is the opening paragraph: 



Looking over the recently is'sued work on ' Geol- 

 ogy/ by Professors Chamberlin and Salisbury, I 

 was surprised and disappointed to learn that in 

 this voluminous publication of nearly two thou- 

 sand pages, many of which are devoted to consid- 

 erations of causes leading up to the ice age, the 

 name of Dr. Marsden Manson is not to be found. 



We, in our turn, are surprised that before 

 going into print with this statement. Dr. 

 Schaeberle did not consult the index of the 

 work in question, where, in its appropriate 

 place, he might have found: 



Manson, M., cited, iii, 445. 



Referring to the page named, he would have 

 found a section devoted to the cloud hypoth- 

 esis and the wind hypothesis. Under the 



cloud hypothesis the following references are 

 given : 



Manson, Am. Geol., Vol. XIV., 1894, pp. 192- 

 194; Vol. XXIII., 1899, pp. 44-57; and Vol. 

 XXIV., 1899, pp. 93-120, 157-180, 205-209. 



The discussion was, to be sure, generic 

 rather than specific, and was directed toward 

 the evolution of hypotheses concordant with 

 the present state of discovery and inquiry, 

 rather than retrospective. It was no part of 

 the policy of the authors in preparing the 

 work to bring up the specific views of an 

 individual writer only to throw them down, 

 unless wide acceptance required their consid- 

 eration. Especially did the authors endeavor 

 to avoid the adverse criticism of individual 

 views when the ground had been adequately 

 covered already by generic treatment. They, 

 therefore, saw no sufficient reason for reciting 

 and criticizing the special view of Dr. Man- 

 son that the earth, from the Archean to the 

 Middle Tertiary, was shrouded in a mantle of 

 clouds so deep, dense, universal and persistent 

 that the sun had no effective differential influ- 

 ence on the temperature at the earth's surface, 

 which was maintained by internal heat, and 

 his conclusion that the Pleistocene glaciation 

 was an incident of the transition from this 

 cloud-shrouded era to the present one and was 

 hence the only true glacial period. The au- 

 thors had recited with care the evidence that 

 there were other and much earlier glaciations 

 whose extent and character raised even more 

 exacting climatological questions than the 

 Pleistocene glaciation. They had cited, in 

 their appropriate places, the paleobotanical 

 evidences of open and varied skies and diversi- 

 ties of atmosphere, specifically noting that the 

 upper sides of leaves of different genera even 

 in Paleozoic times were provided with palisade 

 cells as a protection against too great intensity 

 of sunlight. They had discussed at length 

 and repeatedly, in the proper places, the great 

 evaporation deposits and their associates, to- 

 gether with the related evidences, both phys- 

 ical and organic, of wide-spread and recurrent 

 aridity, with its obvious implication of open 

 and diversified skies and of effective solar 

 action. It had been specifically pointed out 



