Item 62 - Letter from John Herschel

4 pp

John and Margaret Herschel will be delighted to see William and Cordelia Whewell on Tuesday: However because they are preparing for the scarlet fever currently ravaging the neighbourhood, 'we cannot ask you to become our inmates'. JH has received WW's resume of letters on the glacier theories. He thought he understood the subject when the controversy first broke out, but it 'seems to me now encumbered with so many considerations that I am not sure I do understand it'. JH thinks that besides solid fluid and viscous bodies the subject has another class belonging to it: 'Bodies easily disrupted and readily reuniting by stickage. The plasticity of most snow is very evidently of this kind - it is very evident on crushing up masses of it that it yields and Retoughens by sudden jerks. - I do not perceive that this has been noted in the controversy'.