BEHAVIOUR OF ICE UNDER BRAMAH S PRESS. XV 



referred. This practical argument was the more acceptable, 

 because the absence of such a power of being moulded under 

 intense, rapid pressure had been urged as an objection to my 

 theory by MM. Sehlagintweit, in their work on this subject.* 

 The fact is, that the confining of the ice by lateral compression, 

 whether in the great experiment of nature (in glaciers), or on 

 the small scale, is, generally speaking, requisite to its success. 

 I had, however, somewhat underrated the difficulties which my 

 opinions had to contend with. The new generation of thinkers, 

 whose powers of investigation were now first to be exercised 

 on the theory of glaciers, had to review and discuss all the pre- 

 liminary objections which fifteen years before had furnished the 

 weapons of the opponents of " plasticity " as a property of ice 

 on the great scale. Having said all that I could urge on that 

 subject, I had left my case with a calm and reasonable confi- 

 dence that Time would be the ablest advocate of my cause. I 

 never replied to MM. Schlagintweit's appeal to the evidence 

 derived from the pulverization of ice under Bramah's press,t 

 the reply being the very same as I had already made several 

 times to the popular argument derived from the fragility of 

 ice. It appeared to me that the difficulties felt by Dr. Tyndall 

 and Mr. Huxley, in admitting my theory, even after the inge- 

 nious experiments of the former had demonstrated on the small 

 scale the moulding power of ice, which I had long before 

 asserted to be unquestionably true on the large scale, were also 

 such as a longer familiarity with the subject, and perhaps a more 



* Untersuchungen iiber die Physikalische Geographic der Alpen, pp. 24, 122. 



f In this case the most extravagant distortion was sought to be produced in a 

 few moments of time. Whilst in the glacier, an almost inappreciable distortion 

 (for small areas or hand specimens) is produced in periods of many days or weeks. 

 Very probably also, MM. Sehlagintweit operated at temperatures considerably 

 below the freezing-point, otherwise they could hardly fail to have obtained the same 

 results as Dr. Tyndall. 



