142 Chronicles of Science. [Jan., 



The composition of the water in the larger basin closely resembled the 

 other, differing only in containing more organic matter. The most 

 noticeable feature is the large amount of sulphate of lime. In this 

 respect the Spa spring of Windsor, Nova Scotia, is allied to those of 

 Wilmot, as it contains 106*21 grains of sulphate of lime to the gallon. 

 The professor remarks that analyses made on larger quantities than he 

 had at command might reveal the presence of other ingredients. 



Geology. — The last annual address to the Montreal Natural History 

 Society, was given by Principal Dawson, president. After glancing 

 at the scientific work of the Society, and expressing his admiration of 

 the recently published Report of the Geological Survey of Canada, he 

 proceeded to refer to a few points in Canadian Geology, to which the 

 Report directs attention. The first was the discovery of fossils in the 

 lower part of the Laurentian rocks, a discovery, he remarked, which 

 will be " one of the brightest gems in the scientific crown of the Geo- 

 logical Survey of Canada." He referred to the subdivisions of the 

 Laurentian rocks as forming a cycle of deposits similar to others found 

 in the scale of formations. This subject deserves a more careful study 

 as a means of settling the sequence of oscillations of land and water 

 in connection with the succession of life. It may eventually aid in 

 establishing more precise views of the dynamics of Geology and of the 

 lapse of geological time. 



He next referred to the supposed causes of the deposition of the 

 boulder drift of Canada. The iceberg theory has lately been giving 

 way before a reassertion of the doctrine that land-glaciers have been 

 the principal agents in the distribution of the boulder-drift and in the 

 erosions with which it was accompanied. He had been unable, how- 

 ever, to receive the latter theory, being convinced it was not in ac- 

 cordance with the facte he himself had observed in Nova Scotia and in 

 Canada. The Report supported him in the belief that glaciers could 

 scarcely have been the agents in the striation of Canadian rocks, the 

 transport of boulders, or the excavation of lake-basins. Amongst the 

 reasons for this opinion he gave the following : — 



1. It is difficult to suppose a universal covering of ice in con- 

 nection with a wide-spread continent in a temperate latitude. Even if 

 these regions of North America were elevated into a table-land, its 

 breadth would secure a sufficient summer heat to melt away the ice, 

 except from high mountain peaks. There is no fact to supj)ort the 

 alternative suppositions of the existence of immense mountain chains 

 now disappeared, or an unexampled degree of cold from astronomical 

 causes. He rejected Dr. Frankland's theory of a sea with a higher 

 temperature, as inconsistent with the evidence of fossils, and as insuf- 

 ficient to account for the effects. 



2. It seems physically impossible that an immense sheet of ice, 

 such as supposed, could move over an uneven surface, striating it in 

 directions uniform over vast areas, and often different from the present 

 inclinations of the surface ; whilst, if motionless, it could not produce 

 striations. 



3. The transport of boulders to great distances, and the lodgment 



