Item 66 - James David Forbes to William Whewell

Brodick, Arran - Thanks WW for his suggestions regarding the proofs to his forthcoming article defending his glacier theory against William Hopkins criticisms [see JDF to WW, 2 Apr. 1845], and has consequently 'not only adopted these, but softened the expressions throughout almost every part of the article...I added a P.S...on the subject of his remarks on my models and experiments with his own. As usual he simply denies whatever does not suit him, such as the striated structure being produced by the Differential motions. His own experiments were made by moving the centre of his glacier mechanically not by gravity or the reaction of the parts of the model upon one another; and he states that in comparing the Results with his Theory, it is immaterial in what manner the movement was produced. Am I not thus perfectly justified in affirming that such experiments being irrespective of the cause of motion cannot affirm one cause rather than another'.