Branner.] d54 [Feb. 19, 



From the first, or lower hole the debris was all removed by the mining 

 company, and before it was employed as an air-shaft, it could easily be 

 examined both from above and below. The general profile of this hole 

 along its greatest diameter is rudely that of an inverted riding-boot, the 

 toe pointing about N. 80° E. It is thirty-four feet deep, and, at the top, 

 about twenty feet wide in its smallest diameter, while its longest diameter 

 — the length of the foot of the boot — is not known, the drift filling this 

 prolongation never having been removed. It is not cut straight down, 

 but leans considerably in the direction of the greatest diameter, that is, N. 

 80° E. In a foot-note on page 111 of Report Z, Professor Lesley refers to 

 this first pot-hole (the second one not having been discovered at that 

 time), and expresses the opinion that it is a glacial pot-hole, caused by the 

 water falling over a crevasse in the glacier. After having gone over the 

 ground repeatedly, and after having made a thorough study of the topo- 

 graphy of this region, and of what appear to be all the questions that 

 throw any light upon the subject, the more -firmly am I convinced that 

 his is the true and only possible explanation of it. 



The theory advanced by Mr. Ashburner, was to the effect that this first 

 hole was made by water flowing down the hollow in which it is situated, 

 at a time when the stream was larger than it is at present, or by a stream 

 coming from the direction of the Callender gap. 



In regard to the latter suggestion, it may be replied, that, whatever the 

 possibilities or probabilities may be of a stream having, at any time, 

 flowed into the valley through the Callender gap, the position, inclination, 

 and the direction of the greatest diameter of the top of the pot-hole pre- 

 clude the possibility of its having been formed by a stream from such a 

 quarter. The inclination and prolongation of the top of the hole point 

 about N. 80° E., while the Callender gap lies N. 55° W. from this place. 



That a pot-hole of such dimensions could not possibly have been made 

 by the stream that now runs down through the hollow in which the hole 

 occurs, is too plain to require demonstration ; and indeed no such claim, as 

 far as I am aware, has been made. That this stream was once much larger 

 than at present is doubtless true, but, with the present topography, the 

 greatest possible area drained into the hole is less than a quarter of a square 

 mile, or, to speak more exactly, twenty-lhree hundredths (.23) of a square 

 mile. The torrential rains of the tropics would not be sufficient to produce, 

 upon this surface, a stream big enough to grind out such a pot-hole. If 

 we suppose that the two streams that cross the Callender gap road north 

 of the hole, and the upper part of Tinklepaugh creek may have, at one 

 time, drained into this hole (and, while the first two may have done so, 

 there is scarcely a possibility that this last ever did), the greatest possible 

 area so draining would have been less than two square miles, or, more 

 precisely, 1.85 square miles.* 



* These calculations are based upon the topographical map of this region made 

 by the writer, and are known to be trustworthy. 



