SUPERFICIAL GEOLOGY OF DUNDAS VALLEY. I03 



ism, contained in the magnet, induces opposite magnetism in the ends 

 of the needle, attracting them, so that they lie in a horizontal plane, 

 with their ends toward either pole of the magnet. Their position 

 causes the brass pointer before mentioned, to take up a vertical posi- 

 tion, opposite a zero mark, on the quadrant. To test the current of 

 any machine, the conductors are attached to the binding posts. On 

 the armature being set in motion, the passage of the current around 

 the box sets up a magnetic whirl, which causes the needles to take 

 up a new position, dependent upon its intensity, which is indicated 

 by the pointer on the quadrant, which is the measure of the intensity 

 of the current. Its present arrangement is intended as a measure of 

 intensity, or quantity only. To measure electro-motive force, it is 

 only necessary to substitute for the present box, one wound with 

 many turns of fine wire, offering a resistence of 300 or 400 ohms. 

 The needle will then indicate, as before, the electro-motive force of 

 the current, It is necessary, before using the instrument, to com- 

 pare it with some well known standard of resistance, in order to be 

 able to measure the intensity or electro-motive force of any current. 



SUPERFICIAL GEOLOGY OF DUNDAS VALLEY AND 

 WESTERN ANCASTER. 



BY WM. KENNEDY. 



In 1879, Mr. J. F Carll, of the second Geological Survey of 

 Pennsylvania, presented a report on the pre-glacial and post-glacial 

 drainage of the Lake Erie country, in which it was shown that a 

 great number of the streams of the northern part of Pennsylvania, 

 in pre-glacial times, flowed into Lake Erie.* 



The great difficulty with Mr. Carll's deductions was the finding 

 a necessary outlet for Lake Erie. 



On 1 8th March, I881, Professor Spencer, of King's College, 

 Windsor, Nova Scotia, read a paper on "The discovery of the pre- 

 glacial outlet of the basin of Lake Erie into Lake 'Ontario," before 

 the American Philosophical Society, and on the 8th December last, 

 Professor Spencer read a paper on the same subject, before the 

 Hamilton Association. On the formation of the Geological Section 

 of this Association, it was understood that the Geology of the dis- 



Report Second Geological Survey of Pennsylvania, III. page 330 et Seq. 



