166 Thk Ottawa Naturalist. 



members of our club. These shell deposits are found at many points 

 along the hills around Ottawa and away up the river to the west at 

 elevations of hundreds of feet above present sea level, and show that the 

 deposits of the>e portions of the present crust of the earth were due to 

 the series of rhythmic pulsations which seem to be constantly going on, 

 and by which at one time, the surface is raised to a considerable eleva- 

 tion above tide water and then gradually becomes submerged till the 

 ocean waves wash the sides of our highest hills. 



It will be readily admitted by everyone conversant with the s-ludy 

 of Geology, that, like all other branches of science, it is extremely pro- 

 gressive in its ttndency ; but though the new facts acquired year by 

 year, through our recent sources of knowledge, have led to many changes 

 of view as to the origin, history and manner of formations of the com- 

 ponent parts of the earth's crust, it should not be assumed that as a 

 consequence any discredit should attach to the conscientious woik of 

 the pioneers in the science, but rather the greater credit should in many 

 cases be given, in that they, with such poor materials at their disposal and 

 such a lack of facilities at their command for investigation, should have 

 been able to accomplish so much, and to obtain results so generally 

 satisfactory to those who have since studied the rocks in the light of 

 modern science. 



