WARPING OF THE IROQUOIS BEACH 



169 



this view, my friend Dr Ellis has aided me in working out a curve to 

 represent the differential elevation of the region. The hights of the beach 

 above present sealevel were taken from Spencer's History of the Great 

 Lakes and used as ordinates, while distances from Hamilton, at the west 

 end of the lake, served as abscissse. It was found, to our surprise, that 

 the direction northeast did not bring the readings into anything like 

 harmony, those south of lake Ontario being too low as compared with 

 those to the north. After numerous trials the direction north 17 degrees 

 east was observed to harmonize the elevations given by Spencer in the 

 most satisfactory way, and the diagram resulting is reproduced here. It 



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Figure 2. — Curve of Elevation of Iroquois Beach. 

 Projected on a vertical plane running N. 17° E. 



will be noticed that the determinations as a whole form an evident curve 

 rising at a rapidly increasing ratio in the direction of north 17 degrees east. 

 The irregularities may be accounted for probably by the fact that in some 

 cases the hight of the crest of a bar was measured ; in others that of the 

 plain at the foot of a shore cliff. It should be added that Mr Gilbert 

 finds several beach lines on the north side of the lake, near its eastern 

 end, having quite a range of elevation, and thinks there are records of 

 two intersecting water planes. As the records of his work have not 

 reached me, they can not be made use of here, and the curve is given as 



